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Danilevicz IM, van Hees VT, van der Heide FCT, Jacob L, Landré B, Benadjaoud MA, Sabia S. Measures of fragmentation of rest activity patterns: mathematical properties and interpretability based on accelerometer real life data. BMC Med Res Methodol 2024; 24:132. [PMID: 38849718 PMCID: PMC11157888 DOI: 10.1186/s12874-024-02255-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 05/24/2024] [Indexed: 06/09/2024] Open
Abstract
Accelerometers, devices that measure body movements, have become valuable tools for studying the fragmentation of rest-activity patterns, a core circadian rhythm dimension, using metrics such as inter-daily stability (IS), intradaily variability (IV), transition probability (TP), and self-similarity parameter (named α ). However, their use remains mainly empirical. Therefore, we investigated the mathematical properties and interpretability of rest-activity fragmentation metrics by providing mathematical proofs for the ranges of IS and IV, proposing maximum likelihood and Bayesian estimators for TP, introducing the activity balance index (ABI) metric, a transformation of α , and describing distributions of these metrics in real-life setting. Analysis of accelerometer data from 2,859 individuals (age=60-83 years, 21.1% women) from the Whitehall II cohort (UK) shows modest correlations between the metrics, except for ABI and α . Sociodemographic (age, sex, education, employment status) and clinical (body mass index (BMI), and number of morbidities) factors were associated with these metrics, with differences observed according to metrics. For example, a difference of 5 units in BMI was associated with all metrics (differences ranging between -0.261 (95% CI -0.302, -0.220) to 0.228 (0.18, 0.268) for standardised TP rest to activity during the awake period and TP activity to rest during the awake period, respectively). These results reinforce the value of these rest-activity fragmentation metrics in epidemiological and clinical studies to examine their role for health. This paper expands on a set of methods that have previously demonstrated empirical value, improves the theoretical foundation for these methods, and evaluates their empirical use in a large dataset.
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Affiliation(s)
- Ian Meneghel Danilevicz
- Université Paris Cité, INSERM, U1153, CRESS, Epidemiology of Ageing and Neurodegenerative Diseases, 10 Av de Verdun, 75010, Paris, France
| | | | - Frank C T van der Heide
- Université Paris Cité, INSERM, U1153, CRESS, Epidemiology of Ageing and Neurodegenerative Diseases, 10 Av de Verdun, 75010, Paris, France
| | - Louis Jacob
- Université Paris Cité, INSERM, U1153, CRESS, Epidemiology of Ageing and Neurodegenerative Diseases, 10 Av de Verdun, 75010, Paris, France
| | - Benjamin Landré
- Université Paris Cité, INSERM, U1153, CRESS, Epidemiology of Ageing and Neurodegenerative Diseases, 10 Av de Verdun, 75010, Paris, France
| | - Mohamed Amine Benadjaoud
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), 31 Av Division Leclerc, 92260, Fontenay-Aux-Roses, France
| | - Séverine Sabia
- Université Paris Cité, INSERM, U1153, CRESS, Epidemiology of Ageing and Neurodegenerative Diseases, 10 Av de Verdun, 75010, Paris, France.
- Department of Epidemiology and Public Health, University College London, London, UK.
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Faraci FM, Scheer FA. Hypertension: Causes and Consequences of Circadian Rhythms in Blood Pressure. Circ Res 2024; 134:810-832. [PMID: 38484034 PMCID: PMC10947115 DOI: 10.1161/circresaha.124.323515] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 02/16/2024] [Indexed: 03/19/2024]
Abstract
Hypertension is extremely common, affecting approximately 1 in every 2 adults globally. Chronic hypertension is the leading modifiable risk factor for cardiovascular disease and premature mortality worldwide. Despite considerable efforts to define mechanisms that underlie hypertension, a potentially major component of the disease, the role of circadian biology has been relatively overlooked in both preclinical models and humans. Although the presence of daily and circadian patterns has been observed from the level of the genome to the whole organism, the functional and structural impact of biological rhythms, including mechanisms such as circadian misalignment, remains relatively poorly defined. Here, we review the impact of daily rhythms and circadian systems in regulating blood pressure and the onset, progression, and consequences of hypertension. There is an emphasis on the impact of circadian biology in relation to vascular disease and end-organ effects that, individually or in combination, contribute to complex phenotypes such as cognitive decline and the loss of cardiac and brain health. Despite effective treatment options for some individuals, control of blood pressure remains inadequate in a substantial portion of the hypertensive population. Greater insight into circadian biology may form a foundation for novel and more widely effective molecular therapies or interventions to help in the prevention, treatment, and management of hypertension and its related pathophysiology.
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Affiliation(s)
- Frank M. Faraci
- Department of Internal Medicine, Francois M. Abboud Cardiovascular Center, Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1081
- Department of Neuroscience and Pharmacology, Francois M. Abboud Cardiovascular Center, Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1081
| | - Frank A.J.L. Scheer
- Division of Sleep Medicine, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, 02115
- Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, Massachusetts, 02115
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3
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Reid KJ, Ingram LT, Jimenez M, Orban ZS, Abbott SM, Grimaldi D, Knutson KL, Zee PC, Koralnik IJ, Maas MB. Impact of sleep disruption on cognitive function in patients with postacute sequelae of SARS-CoV-2 infection: initial findings from a Neuro-COVID-19 clinic. SLEEP ADVANCES : A JOURNAL OF THE SLEEP RESEARCH SOCIETY 2024; 5:zpae002. [PMID: 38370438 PMCID: PMC10873785 DOI: 10.1093/sleepadvances/zpae002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 12/27/2023] [Indexed: 02/20/2024]
Abstract
Introduction Fatigue, brain fog, and sleep disturbance are among the most common symptoms of postacute sequelae of SARS-CoV-2 infection (PASC). We sought to determine the impact of sleep disruption on cognition and quality of life in patients with neurologic manifestations of PASC (Neuro-PASC). Methods Thirty-nine patients were recruited from Neuro-COVID-19 clinic. Mean age was 48.1 years, 71.8% were female, and 82% were never hospitalized for COVID-19. Patients were evaluated via clinical assessment, quality-of-life measures in domains of cognitive function, fatigue, sleep disturbance, anxiety, and depression, NIH Toolbox cognitive tests, and 7 days of wrist actigraphy. Results The median number of neurologic symptoms attributed to PASC was 6, with brain fog being the most common in 89.7%. Regarding non-neurologic symptoms, 94.9% complained of fatigue and 74.4% of insomnia. Patients reported significant impairment in all quality-of-life domains and performed worse in a task of attention compared to a normative US population. Actigraphy showed Neuro-PASC patients had lower sleep efficiency, longer sleep latency (both p < 0.001), and later sleep midpoint (p = 0.039) compared to 71 age-matched healthy controls with no PASC history. Self-reported cognitive symptoms correlated with the severity of fatigue (p < 0.001), anxiety (p = 0.05), and depression (p < 0.01). Objective evidence of sleep disruption measured by wakefulness after sleep onset, sleep efficiency, and latency were associated with decreased performance in attention and processing speed. Conclusion Prospective studies including larger populations of patients are needed to fully determine the interplay of sleep disruption on the cognitive function and quality of life of patients with PASC.
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Affiliation(s)
- Kathryn J Reid
- Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
- Center for Circadian and Sleep Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Louis T Ingram
- Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
- Center for Circadian and Sleep Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Millenia Jimenez
- Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Zachary S Orban
- Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Sabra M Abbott
- Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
- Center for Circadian and Sleep Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Daniela Grimaldi
- Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
- Center for Circadian and Sleep Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Kristen L Knutson
- Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
- Center for Circadian and Sleep Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Phyllis C Zee
- Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
- Center for Circadian and Sleep Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Igor J Koralnik
- Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Mathew B Maas
- Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
- Center for Circadian and Sleep Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
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Cerasa A. Fractals in Neuropsychology and Cognitive Neuroscience. ADVANCES IN NEUROBIOLOGY 2024; 36:761-778. [PMID: 38468062 DOI: 10.1007/978-3-031-47606-8_38] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
The fractal dimension of cognition refers to the idea that the cognitive processes of the human brain exhibit fractal properties. This means that certain patterns of cognitive activity, such as visual perception, memory, language, or problem-solving, can be described using the mathematical concept of fractal dimension.The idea that cognition is fractal has been proposed by some researchers as a way to understand the complex, self-similar nature of the human brain. However, it's a relatively new idea and is still under investigation, so it's not yet clear to what extent cognitive processes exhibit fractal properties or what implications this might have for our understanding of the brain and clinical practice. Indeed, the mission of the "fractal neuroscience" field is to define the characteristics of fractality in human cognition in order to differently characterize the emergence of brain disorders.
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Affiliation(s)
- Antonio Cerasa
- Institute for Biomedical Research and Innovation, National Research Council, IRIB-CNR, Messina, Italy
- S. Anna Institute, Crotone, Italy
- Pharmacotechnology Documentation and Transfer Unit, Preclinical and Translational Pharmacology, Department of Pharmacy, Health Science and Nutrition, University of Calabria, Arcavacata, Italy
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Sun H, Li P, Gao L, Yang J, Yu L, Buchman AS, Bennett DA, Westover MB, Hu K. Altered Motor Activity Patterns within 10-Minute Timescale Predict Incident Clinical Alzheimer's Disease. J Alzheimers Dis 2024; 98:209-220. [PMID: 38393904 PMCID: PMC10977378 DOI: 10.3233/jad-230928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/30/2023] [Indexed: 02/25/2024]
Abstract
Background Fractal motor activity regulation (FMAR), characterized by self-similar temporal patterns in motor activity across timescales, is robust in healthy young humans but degrades with aging and in Alzheimer's disease (AD). Objective To determine the timescales where alterations of FMAR can best predict the clinical onset of AD. Methods FMAR was assessed from actigraphy at baseline in 1,077 participants who had annual follow-up clinical assessments for up to 15 years. Survival analysis combined with deep learning (DeepSurv) was used to examine how baseline FMAR at different timescales from 3 minutes up to 6 hours contributed differently to the risk for incident clinical AD. Results Clinical AD occurred in 270 participants during the follow-up. DeepSurv identified three potential regions of timescales in which FMAR alterations were significantly linked to the risk for clinical AD: <10, 20-40, and 100-200 minutes. Confirmed by the Cox and random survival forest models, the effect of FMAR alterations in the timescale of <10 minutes was the strongest, after adjusting for covariates. Conclusions Subtle changes in motor activity fluctuations predicted the clinical onset of AD, with the strongest association observed in activity fluctuations at timescales <10 minutes. These findings suggest that short actigraphy recordings may be used to assess the risk of AD.
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Affiliation(s)
- Haoqi Sun
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Peng Li
- Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Boston, MA, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Lei Gao
- Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Boston, MA, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Jingyun Yang
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Lei Yu
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Aron S. Buchman
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - David A. Bennett
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, USA
| | | | - Kun Hu
- Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Boston, MA, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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6
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Blodgett JM, Ahmadi M, Stamatakis E, Rockwood K, Hamer M. Fractal complexity of daily physical activity and cognitive function in a midlife cohort. Sci Rep 2023; 13:20340. [PMID: 37990028 PMCID: PMC10663528 DOI: 10.1038/s41598-023-47200-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 11/10/2023] [Indexed: 11/23/2023] Open
Abstract
High stability of fluctuation in physiological patterns across fixed time periods suggest healthy fractal complexity, while greater randomness in fluctuation patterns may indicate underlying disease processes. The importance of fractal stability in mid-life remains unexplored. We quantified fractal regulation patterns in 24-h accelerometer data and examined associations with cognitive function in midlife. Data from 5097 individuals (aged 46) from the 1970 British Cohort Study were analyzed. Participants wore thigh-mounted accelerometers for seven days and completed cognitive tests (verbal fluency, memory, processing speed; derived composite z-score). Detrended fluctuation analysis (DFA) was used to examine temporal correlations of acceleration magnitude across 25 time scales (range: 1 min-10 h). Linear regression examined associations between DFA scaling exponents (DFAe) and each standardised cognitive outcome. DFAe was normally distributed (mean ± SD: 0.90 ± 0.06; range: 0.72-1.25). In males, a 0.10 increase in DFAe was associated with a 0.30 (95% Confidence Interval: 0.14, 0.47) increase in composite cognitive z-score in unadjusted models; associations were strongest for verbal fluency (0.10 [0.04, 0.16]). Associations remained in fully-adjusted models for verbal fluency only (0.06 [0.00, 0.12]). There was no association between DFA and cognition in females. Greater fractal stability in men was associated with better cognitive function. This could indicate mechanisms through which fractal complexity may scale up to and contribute to cognitive clinical endpoints.
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Affiliation(s)
- Joanna M Blodgett
- Institute of Sport Exercise and Health, Division of Surgery and Interventional Science, University College London, London, UK.
| | - Matthew Ahmadi
- School of Health Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
- Mackenzie Wearables Research Hub, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Emmanuel Stamatakis
- School of Health Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
- Mackenzie Wearables Research Hub, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Kenneth Rockwood
- Geriatric Medicine Research, Department of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Mark Hamer
- Institute of Sport Exercise and Health, Division of Surgery and Interventional Science, University College London, London, UK
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Danilevicz IM, van Hees VT, van der Heide F, Jacob L, Landré B, Benadjaoud MA, Sabia S. Measures of fragmentation of rest activity patterns: mathematical properties and interpretability based on accelerometer real life data. RESEARCH SQUARE 2023:rs.3.rs-3543711. [PMID: 37986973 PMCID: PMC10659546 DOI: 10.21203/rs.3.rs-3543711/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Accelerometers, devices that measure body movements, have become valuable tools for studying the fragmentation of rest-activity patterns, a core circadian rhythm dimension, using metrics such as inter-daily stability (IS), intradaily variability (IV), transition probability (TP), and self-similarity parameter (named α ). However, their use remains mainly empirical. Therefore, we investigated the mathematical properties and interpretability of rest-activity fragmentation metrics by providing mathematical proofs for the ranges of IS and IV, proposing maximum likelihood and Bayesian estimators for TP, introducing the activity balance index metric, an adaptation of α , and describing distributions of these metrics in real-life setting. Analysis of accelerometer data from 2,859 individuals (age=60-83 years, 21.1% women) from the Whitehall II cohort (UK) shows modest correlations between the metrics, except for ABI and α . Sociodemographic (age, sex, education, employment status) and clinical (body mass index (BMI), and number of morbidities) factors were associated with these metrics, with differences observed according to metrics. For example, a difference of 5 units in BMI was associated with all metrics (differences ranging between -0.261 (95% CI -0.302, -0.220) to 0.228 (0.18, 0.268) for standardised TP rest to activity during the awake period and TP activity to rest during the awake period, respectively). These results reinforce the value of these rest-activity fragmentation metrics in epidemiological and clinical studies to examine their role for health. This paper expands on a set of methods that have previously demonstrated empirical value, improves the theoretical foundation for these methods, and evaluates their empirical worth in a large dataset.
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Affiliation(s)
- Ian Meneghel Danilevicz
- Université Paris Cité, INSERM, U1153, CRESS, Epidemiology of Ageing and Neurodegenerative Diseases, 10 Av de Verdun, 75010, Paris, France
| | | | - Frank van der Heide
- Université Paris Cité, INSERM, U1153, CRESS, Epidemiology of Ageing and Neurodegenerative Diseases, 10 Av de Verdun, 75010, Paris, France
| | - Louis Jacob
- Université Paris Cité, INSERM, U1153, CRESS, Epidemiology of Ageing and Neurodegenerative Diseases, 10 Av de Verdun, 75010, Paris, France
| | - Benjamin Landré
- Université Paris Cité, INSERM, U1153, CRESS, Epidemiology of Ageing and Neurodegenerative Diseases, 10 Av de Verdun, 75010, Paris, France
| | - Mohamed Amine Benadjaoud
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), 31 Av Division Leclerc, 92260, Fontenay-Aux-Roses, France
| | - Séverine Sabia
- Université Paris Cité, INSERM, U1153, CRESS, Epidemiology of Ageing and Neurodegenerative Diseases, 10 Av de Verdun, 75010, Paris, France
- Department of Epidemiology and Public Health, University College London, London, United Kingdom
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Yilmaz A, Li P, Kalsbeek A, Buijs RM, Hu K. Differential Fractal and Circadian Patterns in Motor Activity in Spontaneously Hypertensive Rats at the Stage of Prehypertension. Adv Biol (Weinh) 2023; 7:e2200324. [PMID: 37017509 DOI: 10.1002/adbi.202200324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 03/03/2023] [Indexed: 04/06/2023]
Abstract
One possible pathological mechanism underlying hypertension and its related health consequences is dysfunction of the circadian system-a network of coupled circadian clocks that generates and orchestrates rhythms of ≈24 h in behavior and physiology. To better understand the role of circadian function during the development of hypertension, circadian regulation of motor activity is investigated in spontaneously hypertensive rats (SHRs) before the onset of hypertension and in their age-matched controls-Wistar Kyoto rats (WKYs). Two complementary properties in locomotor activity fluctuations are examined to assessthe multiscale regulatory function of the circadian control network: 1) rhythmicity at ≈24 h and 2) fractal patterns-similar temporal correlation at different time scales (≈0.5-8 h). Compared to WKYs, SHRs have more stable and less fragmented circadian activity rhythms but the changes in the rhythms (e.g., period and amplitude) from constant dark to light conditions are reduced or opposite. SHRs also have altered fractal activity patterns, displaying activity fluctuations with excessive regularity at small timescales that are linked to rigid physiological states. These different rhythmicity/fractal patterns and their different responses to light in SHRs indicate that an altered circadian function may be involved in the development of hypertension.
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Affiliation(s)
- Ajda Yilmaz
- Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, 1105BA, The Netherlands
| | - Peng Li
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, 02115, USA
- Division of Sleep Medicine, Department of Medicine, Harvard Medical School, 221 Longwood Avenue, Boston, MA, 02115, USA
| | - Andries Kalsbeek
- Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, 1105BA, The Netherlands
- Department of Endocrinology and Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, 1105AZ, The Netherlands
- Laboratory of Endocrinology, Amsterdam Gastroenterology, Endocrinology Metabolism (AGEM), Amsterdam UMC, Amsterdam, 1105AZ, Netherlands
| | - Ruud M Buijs
- Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, 1105BA, The Netherlands
- Department of Cell Biology and Physiology, Instituto Investigaciones Biomedicas, Universidad Nacional Autonoma de Mexico, Mexico City, 04510, Mexico
| | - Kun Hu
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, 02115, USA
- Division of Sleep Medicine, Department of Medicine, Harvard Medical School, 221 Longwood Avenue, Boston, MA, 02115, USA
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Vairavan S, Rashidisabet H, Li QS, Ness S, Morrison RL, Soares CN, Uher R, Frey BN, Lam RW, Kennedy SH, Trivedi M, Drevets WC, Narayan VA. Personalized relapse prediction in patients with major depressive disorder using digital biomarkers. Sci Rep 2023; 13:18596. [PMID: 37903878 PMCID: PMC10616277 DOI: 10.1038/s41598-023-44592-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 10/10/2023] [Indexed: 11/01/2023] Open
Abstract
Major depressive disorder (MDD) is a chronic illness wherein relapses contribute to significant patient morbidity and mortality. Near-term prediction of relapses in MDD patients has the potential to improve outcomes by helping implement a 'predict and preempt' paradigm in clinical care. In this study, we developed a novel personalized (N-of-1) encoder-decoder anomaly detection-based framework of combining anomalies in multivariate actigraphy features (passive) as triggers to utilize an active concurrent self-reported symptomatology questionnaire (core symptoms of depression and anxiety) to predict near-term relapse in MDD. The framework was evaluated on two independent longitudinal observational trials, characterized by regular bimonthly (every other month) in-person clinical assessments, weekly self-reported symptom assessments, and continuous activity monitoring data with two different wearable sensors for ≥ 1 year or until the first relapse episode. This combined passive-active relapse prediction framework achieved a balanced accuracy of ≥ 71%, false alarm rate of ≤ 2.3 alarm/patient/year with a median relapse detection time of 2-3 weeks in advance of clinical onset in both studies. The study results suggest that the proposed personalized N-of-1 prediction framework is generalizable and can help predict a majority of MDD relapses in an actionable time frame with relatively low patient and provider burden.
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Affiliation(s)
- Srinivasan Vairavan
- Janssen Research & Development, LLC, 1125 Trenton Harbourton Road, Titusville, NJ, 08560, USA.
| | - Homa Rashidisabet
- Department of Bioengineering, University of Illinois Chicago, Chicago, IL, USA
| | - Qingqin S Li
- Janssen Research & Development, LLC, 1125 Trenton Harbourton Road, Titusville, NJ, 08560, USA
| | - Seth Ness
- Janssen Research & Development, LLC, 1125 Trenton Harbourton Road, Titusville, NJ, 08560, USA
| | - Randall L Morrison
- Janssen Research & Development, LLC, 1125 Trenton Harbourton Road, Titusville, NJ, 08560, USA
| | - Claudio N Soares
- Department of Psychiatry, Queen's University School of Medicine, Kingston, ON, Canada
| | - Rudolf Uher
- Department of Psychiatry, Dalhousie University, Halifax, Canada
| | - Benicio N Frey
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, ON, Canada
- Mood Disorders Program, St. Joseph's Healthcare Hamilton, Hamilton, ON, Canada
| | - Raymond W Lam
- Department of Psychiatry, University of British Columbia, Vancouver, Canada
| | - Sidney H Kennedy
- Centre for Depression and Suicide Studies, Unity Health Toronto, Toronto, Canada
- Krembil Neurosciences, University Health Network, Toronto, Canada
- Department of Psychiatry, University of Toronto, Toronto, Canada
| | - Madhukar Trivedi
- Peter O'Donnell Jr. Brain Institute and the Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Wayne C Drevets
- Janssen Research & Development, LLC, 1125 Trenton Harbourton Road, Titusville, NJ, 08560, USA
| | - Vaibhav A Narayan
- Janssen Research & Development, LLC, 1125 Trenton Harbourton Road, Titusville, NJ, 08560, USA
- Davos Alzheimer's Collaborative, Geneva, Switzerland
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10
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Gao L, Li P, Gaykova N, Zheng X, Gao C, Lane JM, Saxena R, Scheer FAJL, Rutter MK, Akeju O, Hu K. Circadian Rest-Activity Rhythms, Delirium Risk, and Progression to Dementia. Ann Neurol 2023; 93:1145-1157. [PMID: 36808743 PMCID: PMC10247440 DOI: 10.1002/ana.26617] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 02/13/2023] [Accepted: 02/16/2023] [Indexed: 02/22/2023]
Abstract
OBJECTIVE Delirium is a complex neurocognitive syndrome suspected to be bidirectionally linked to dementia. Circadian rhythm disturbances likely contribute to dementia pathogenesis, but whether these disturbances are related to delirium risk and progression to all-cause dementia is unknown. METHODS We analyzed continuous actigraphy data from 53,417 middle-aged or older UK Biobank participants during a median 5 years of follow-up. Four measures were used to characterize the 24-hour daily rest-activity rhythms (RARs): normalized amplitude, acrophase representing the peak activity time, interdaily stability, and intradaily variability (IV) for fragmentation of the rhythm. Cox proportional hazards models examined whether RARs predicted incident delirium (n = 551) and progression to dementia (n = 61). RESULTS Suppressed 24-hour amplitude, lowest (Q1) versus highest (Q4) quartile (hazard ratio [HR]Q1 vs Q4 = 1.94, 95% confidence interval [CI] = 1.53-2.46, p < 0.001), and more fragmented (higher IV: HRQ4 vs Q1 = 1.49, 95% CI = 1.18-1.88, p < 0.001) rhythms predicted higher delirium risk, after adjusting for age, sex, education, cognitive performance, sleep duration/disturbances, and comorbidities. In those free from dementia, each hour of delayed acrophase was associated with delirium risk (HR = 1.13, 95% CI = 1.04-1.23, p = 0.003). Suppressed 24-hour amplitude was associated with increased risk of progression from delirium to new onset dementia (HR = 1.31, 95% CI = 1.03-1.67, p = 0.03 for each 1-standard deviation decrease). INTERPRETATION Twenty-four-hour daily RAR suppression, fragmentation, and potentially delayed acrophase were associated with delirium risk. Subsequent progression to dementia was more likely in delirium cases with suppressed rhythms. The presence of RAR disturbances before delirium and prior to progression to dementia suggests that these disturbances may predict higher risk and be involved in early disease pathogenesis. ANN NEUROL 2023;93:1145-1157.
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Affiliation(s)
- Lei Gao
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA, USA
| | - Peng Li
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA, USA
| | - Nicole Gaykova
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, USA
| | - Xi Zheng
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, USA
| | - Chenlu Gao
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
| | - Jacqueline M Lane
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA, USA
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Richa Saxena
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA, USA
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Frank A J L Scheer
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA, USA
- Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, USA
| | - Martin K Rutter
- Division of Diabetes, Endocrinology, and Gastroenterology, University of Manchester, Manchester, UK
- Diabetes Endocrinology and Metabolism Centre, Manchester University National Health Service Foundation Trust, Manchester, UK
| | - Oluwaseun Akeju
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Kun Hu
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
- Broad Institute of Massachusetts Institute of Technology and Harvard University, Cambridge, MA, USA
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11
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Ulsa MC, Xi Z, Li P, Gaba A, Wong PM, Saxena R, Scheer FAJL, Rutter M, Akeju O, Hu K, Gao L. Association of Poor Sleep Burden in Middle Age and Older Adults With Risk for Delirium During Hospitalization. J Gerontol A Biol Sci Med Sci 2022; 77:507-516. [PMID: 34558609 PMCID: PMC8893188 DOI: 10.1093/gerona/glab272] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Delirium is a distressing neurocognitive disorder recently linked to sleep disturbances. However, the longitudinal relationship between sleep and delirium remains unclear. This study assessed the associations of poor sleep burden, and its trajectory, with delirium risk during hospitalization. METHODS About 321 818 participants from the UK Biobank (mean age 58 ± 8 years [SD]; range 37-74 years) reported (2006-2010) sleep traits (sleep duration, excessive daytime sleepiness, insomnia-type complaints, napping, and chronotype-a closely related circadian measure for sleep timing), aggregated into a sleep burden score (0-9). New-onset delirium (n = 4 775) was obtained from hospitalization records during a 12-year median follow-up. About 42 291 (mean age 64 ± 8 years; range 44-83 years) had repeat sleep assessment on average 8 years after their first. RESULTS In the baseline cohort, Cox proportional hazards models showed that moderate (aggregate scores = 4-5) and severe (scores = 6-9) poor sleep burden groups were 18% (hazard ratio = 1.18 [95% confidence interval: 1.08-1.28], p < .001) and 57% (1.57 [1.38-1.80], p < .001), more likely to develop delirium, respectively. The latter risk magnitude is equivalent to 2 additional cardiovascular risks. These findings appeared robust when restricted to postoperative delirium and after exclusion of underlying dementia. Higher sleep burden was also associated with delirium in the follow-up cohort. Worsening sleep burden (score increase ≥2 vs no change) further increased the risk for delirium (1.79 [1.23-2.62], p = .002) independent of their baseline sleep score and time lag. The risk was highest in those younger than 65 years at baseline (p for interaction <.001). CONCLUSION Poor sleep burden and worsening trajectory were associated with increased risk for delirium; promotion of sleep health may be important for those at higher risk.
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Affiliation(s)
- Ma Cherrysse Ulsa
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Boston, Massachusetts, USA
| | - Zheng Xi
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Boston, Massachusetts, USA
| | - Peng Li
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Boston, Massachusetts, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Arlen Gaba
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Boston, Massachusetts, USA
| | - Patricia M Wong
- Alpert Medical School of Brown University, Providence, Rhode Island, USA
| | - Richa Saxena
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, USA
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Frank A J L Scheer
- Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts, USA
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Martin Rutter
- Division of Diabetes, Endocrinology & Gastroenterology, The University of Manchester, UK
| | - Oluwaseun Akeju
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, USA
| | - Kun Hu
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Boston, Massachusetts, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Lei Gao
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Boston, Massachusetts, USA
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, USA
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Abstract
Endogenous biological clocks, orchestrated by the suprachiasmatic nucleus, time the circadian rhythms that synchronize physiological and behavioural functions in humans. The circadian system influences most physiological processes, including sleep, alertness and cognitive performance. Disruption of circadian homeostasis has deleterious effects on human health. Neurodegenerative disorders involve a wide range of symptoms, many of which exhibit diurnal variations in frequency and intensity. These disorders also disrupt circadian homeostasis, which in turn has negative effects on symptoms and quality of life. Emerging evidence points to a bidirectional relationship between circadian homeostasis and neurodegeneration, suggesting that circadian function might have an important role in the progression of neurodegenerative disorders. Therefore, the circadian system has become an attractive target for research and clinical care innovations. Studying circadian disruption in neurodegenerative disorders could expand our understanding of the pathophysiology of neurodegeneration and facilitate the development of novel, circadian-based interventions for these disabling disorders. In this Review, we discuss the alterations to the circadian system that occur in movement (Parkinson disease and Huntington disease) and cognitive (Alzheimer disease and frontotemporal dementia) neurodegenerative disorders and provide directions for future investigations in this field.
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Knapen SE, Li P, Riemersma- van der Lek RF, Verkooijen S, Boks MP, Schoevers RA, Hu K, Scheer FA. Fractal biomarker of activity in patients with bipolar disorder. Psychol Med 2021; 51:1562-1569. [PMID: 32234100 PMCID: PMC8208237 DOI: 10.1017/s0033291720000331] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND The output of many healthy physiological systems displays fractal fluctuations with self-similar temporal structures. Altered fractal patterns are associated with pathological conditions. There is evidence that patients with bipolar disorder have altered daily behaviors. METHODS To test whether fractal patterns in motor activity are altered in patients with bipolar disorder, we analyzed 2-week actigraphy data collected from 106 patients with bipolar disorder type I in a euthymic state, 73 unaffected siblings of patients, and 76 controls. To examine the link between fractal patterns and symptoms, we analyzed 180-day actigraphy and mood symptom data that were simultaneously collected from 14 patients. RESULTS Compared to controls, patients showed excessive regularity in motor activity fluctuations at small time scales (<1.5 h) as quantified by a larger scaling exponent (α1 > 1), indicating a more rigid motor control system. α1 values of siblings were between those of patients and controls. Further examinations revealed that the group differences in α1 were only significant in females. Sex also affected the group differences in fractal patterns at larger time scales (>2 h) as quantified by scaling exponent α2. Specifically, female patients and siblings had a smaller α2 compared to female controls, indicating more random activity fluctuations; while male patients had a larger α2 compared to male controls. Interestingly, a higher weekly depression score was associated with a lower α1 in the subsequent week. CONCLUSIONS Our results show sex- and scale-dependent alterations in fractal activity regulation in patients with bipolar disorder. The mechanisms underlying the alterations are yet to be determined.
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Affiliation(s)
- Stefan E. Knapen
- University of Groningen, University Medical Center Groningen, Department of Psychiatry, Research School of Behavioural and Cognitive Neurosciences (BCN), Interdisciplinary Center Psychopathology and Emotion regulation (ICPE). Groningen, the Netherlands
- Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital; and Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts, United States
| | - Peng Li
- Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital; and Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts, United States
| | - Rixt F. Riemersma- van der Lek
- University of Groningen, University Medical Center Groningen, Department of Psychiatry, Research School of Behavioural and Cognitive Neurosciences (BCN), Interdisciplinary Center Psychopathology and Emotion regulation (ICPE). Groningen, the Netherlands
| | - Sanne Verkooijen
- Brain Center Rudolf Magnus, University Medical Center Utrecht, Department of Psychiatry, Utrecht, the Netherlands
| | - Marco P.M. Boks
- Brain Center Rudolf Magnus, University Medical Center Utrecht, Department of Psychiatry, Utrecht, the Netherlands
| | - Robert A. Schoevers
- University of Groningen, University Medical Center Groningen, Department of Psychiatry, Research School of Behavioural and Cognitive Neurosciences (BCN), Interdisciplinary Center Psychopathology and Emotion regulation (ICPE). Groningen, the Netherlands
| | - Kun Hu
- Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital; and Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts, United States
| | - Frank A.J.L. Scheer
- Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital; and Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts, United States
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Gao L, Li P, Gaba A, Musiek E, Ju YS, Hu K. Fractal motor activity regulation and sex differences in preclinical Alzheimer's disease pathology. ALZHEIMER'S & DEMENTIA (AMSTERDAM, NETHERLANDS) 2021; 13:e12211. [PMID: 34189248 PMCID: PMC8220856 DOI: 10.1002/dad2.12211] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 05/18/2021] [Accepted: 05/19/2021] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Degradation in fractal motor activity regulation (FMAR), a measure of multiscale self-similarity of motor control, occurs in aging and accelerates with clinical progression to Alzheimer's disease (AD). Whether FMAR changes occur during the pre-symptomatic phase of the disease in women and men remains unknown. METHODS FMAR was assessed in cognitively normal participants (n = 178) who underwent 7 to 14 days of home actigraphy. Preclinical AD pathology was determined by amyloid imaging-Pittsburgh compound B (PiB) and cerebrospinal fluid (CSF) phosphorylated-tau181 (p-tau) to amyloid beta 42 (Aβ42) ratio. RESULTS Degradation in daytime FMAR was overall significantly associated with preclinical amyloid plaque pathology via PiB+ imaging (beta coefficient β = 0.217, standard error [SE] = 0.101, P = .034) and increasing CSF tau181-Aβ42 ratio (β = 0.220, SE = 0.084, P = .009). In subset analysis by sex, the effect sizes were significant in women for PiB+ (β = 0.279, SE = 0.112, P = .015) and CSF (β = 0.245, SE = 0.094, P = .011) but not in men (both Ps > .05). These associations remained after inclusion of daily activity level, apolipoprotein E ε4 carrier status, and rest/activity patterns. DISCUSSION Changes in daytime FMAR from actigraphy appear to be present in women early in preclinical AD. This may be a combination of earlier pathology changes in females reflected in daytime FMAR, and a relatively underpowered male group. Further studies are warranted to test FMAR as an early noncognitive physiological biomarker that precedes the onset of cognitive symptoms.
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Affiliation(s)
- Lei Gao
- Department of Anesthesia, Critical Care and Pain MedicineMassachusetts General HospitalHarvard Medical SchoolBostonMassachusettsUSA
- Medical Biodynamics ProgramBrigham and Women's HospitalBostonMassachusettsUSA
- Division of Sleep MedicineHarvard Medical SchoolBostonMassachusettsUSA
| | - Peng Li
- Medical Biodynamics ProgramBrigham and Women's HospitalBostonMassachusettsUSA
- Division of Sleep MedicineHarvard Medical SchoolBostonMassachusettsUSA
| | - Arlen Gaba
- Medical Biodynamics ProgramBrigham and Women's HospitalBostonMassachusettsUSA
| | - Erik Musiek
- Department of NeurologyWashington University School of MedicineSt. LouisMissouriUSA
- Knight Alzheimer's Disease Research CenterWashington University School of MedicineSt. LouisMissouriUSA
- Hope Center for Neurological DisordersWashington University School of MedicineSt. LouisMissouriUSA
| | - Yo‐El S. Ju
- Department of NeurologyWashington University School of MedicineSt. LouisMissouriUSA
- Hope Center for Neurological DisordersWashington University School of MedicineSt. LouisMissouriUSA
| | - Kun Hu
- Medical Biodynamics ProgramBrigham and Women's HospitalBostonMassachusettsUSA
- Division of Sleep MedicineHarvard Medical SchoolBostonMassachusettsUSA
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15
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Patel S, Howard D, Chowdhury N, Derieux C, Wellslager B, Yilmaz Ö, French L. Characterization of Human Genes Modulated by Porphyromonas gingivalis Highlights the Ribosome, Hypothalamus, and Cholinergic Neurons. Front Immunol 2021; 12:646259. [PMID: 34194426 PMCID: PMC8236716 DOI: 10.3389/fimmu.2021.646259] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Accepted: 05/20/2021] [Indexed: 12/12/2022] Open
Abstract
Porphyromonas gingivalis, a bacterium associated with periodontal disease, is a suspected cause of Alzheimer's disease. This bacterium is reliant on gingipain proteases, which cleave host proteins after arginine and lysine residues. To characterize gingipain susceptibility, we performed enrichment analyses of arginine and lysine proportion proteome-wide. Genes differentially expressed in brain samples with detected P. gingivalis reads were also examined. Genes from these analyses were tested for functional enrichment and specific neuroanatomical expression patterns. Proteins in the SRP-dependent cotranslational protein targeting to membrane pathway were enriched for these residues and previously associated with periodontal and Alzheimer's disease. These ribosomal genes are up-regulated in prefrontal cortex samples with detected P. gingivalis sequences. Other differentially expressed genes have been previously associated with dementia (ITM2B, MAPT, ZNF267, and DHX37). For an anatomical perspective, we characterized the expression of the P. gingivalis associated genes in the mouse and human brain. This analysis highlighted the hypothalamus, cholinergic neurons, and the basal forebrain. Our results suggest markers of neural P. gingivalis infection and link the cholinergic and gingipain hypotheses of Alzheimer's disease.
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Affiliation(s)
- Sejal Patel
- Krembil Centre for Neuroinformatics, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Derek Howard
- Krembil Centre for Neuroinformatics, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Nityananda Chowdhury
- Department of Oral Health Sciences, Medical University of South Carolina, Charleston, SC, United States
| | - Casey Derieux
- Department of Oral Health Sciences, Medical University of South Carolina, Charleston, SC, United States
| | - Bridgette Wellslager
- Department of Oral Health Sciences, Medical University of South Carolina, Charleston, SC, United States
| | - Özlem Yilmaz
- Department of Oral Health Sciences, Medical University of South Carolina, Charleston, SC, United States
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, United States
| | - Leon French
- Krembil Centre for Neuroinformatics, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Institute for Medical Science, University of Toronto, Toronto, ON, Canada
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16
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Maas MB, Lizza BD, Kim M, Abbott SM, Gendy M, Reid KJ, Zee PC. Stress-Induced Behavioral Quiescence and Abnormal Rest-Activity Rhythms During Critical Illness. Crit Care Med 2021; 48:862-871. [PMID: 32317592 DOI: 10.1097/ccm.0000000000004334] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
OBJECTIVES To characterize acute alterations of circadian and ultradian rest-activity rhythms in critically ill patients and their association with brain dysfunction, systemic multiple organ dysfunction, and melatonin rhythms. DESIGN Prospective study observing a cohort for 48 hours beginning within the first day of ICU admission. SETTING ICUs within an academic medical center. PATIENTS Patients presenting from the community with acute onset of either intracerebral hemorrhage or sepsis as representative neurologic and systemic critical illnesses. Healthy control patients were studied in the community, during hospital bedrest, and during sleep deprivation. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Circadian and ultradian characteristics of rest-activity patterns were measured by wrist actigraphy, severity of neurologic and systemic illness by Glasgow Coma Scale and Sequential Organ Failure Assessment, and central circadian rhythm by melatonin profile. We studied 112 critically ill patients, including 53 with sepsis and 59 with intracerebral hemorrhage, along with 53 control participants. Total daily activity was markedly reduced and rest-activity rhythmicity was undetectable, neither of which was replicated by hospital bedrest in healthy controls. Circadian rest-activity rhythm fragmentation and attenuation and ultradian disorganization was associated with Glasgow Coma Scale and Sequential Organ Failure Assessment in adjusted models. Rest-activity rhythms showed no detectable phase coherence with melatonin rhythms. CONCLUSIONS Critically ill patients rapidly enter a state of behavioral quiescence proportionate to their illness severity with concomitant disturbance of circadian and ultradian rest-activity rhythms and loss of phase coherence with the melatonin rhythm. Quiescence characteristics in rest-activity rhythms were not different in patients with and without delirium, suggesting them to be distinct phenomena. Animal models of severe physiologic stress have shown that specific neural pathway separate from the sleep-wake regulatory pathway induce behavioral quiescence and rest-activity arrhythmia, and facilitate recovery of cellular homeostasis. Whether quiescence is a conserved protective response pathway in humans is not yet understood.
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Affiliation(s)
- Matthew B Maas
- Department of Neurology, Northwestern University, Chicago, IL.,Center for Circadian and Sleep Medicine, Northwestern University, Chicago, IL
| | - Bryan D Lizza
- Department of Pharmacy, Barnes-Jewish Hospital, St. Louis, MO
| | - Minjee Kim
- Department of Neurology, Northwestern University, Chicago, IL.,Center for Circadian and Sleep Medicine, Northwestern University, Chicago, IL
| | - Sabra M Abbott
- Department of Neurology, Northwestern University, Chicago, IL.,Center for Circadian and Sleep Medicine, Northwestern University, Chicago, IL
| | - Maged Gendy
- Department of Neurology, Northwestern University, Chicago, IL.,Center for Circadian and Sleep Medicine, Northwestern University, Chicago, IL
| | - Kathryn J Reid
- Department of Neurology, Northwestern University, Chicago, IL.,Center for Circadian and Sleep Medicine, Northwestern University, Chicago, IL
| | - Phyllis C Zee
- Department of Neurology, Northwestern University, Chicago, IL.,Center for Circadian and Sleep Medicine, Northwestern University, Chicago, IL
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Sleep, rest-activity rhythms and aging: a complex web in Alzheimer's disease? Neurobiol Aging 2021; 104:102-103. [PMID: 33902941 DOI: 10.1016/j.neurobiolaging.2021.02.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 02/19/2021] [Accepted: 02/23/2021] [Indexed: 11/21/2022]
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18
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Vaz JR, Knarr BA, Stergiou N. Gait complexity is acutely restored in older adults when walking to a fractal-like visual stimulus. Hum Mov Sci 2020; 74:102677. [PMID: 33069099 DOI: 10.1016/j.humov.2020.102677] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 08/01/2020] [Accepted: 09/02/2020] [Indexed: 11/25/2022]
Abstract
Typically, gait rehabilitation uses an invariant stimulus paradigm to improve gait related deficiencies. However, this approach may not be optimal as it does not incorporate gait complexity, or in more precise words, the variable fractal-like nature found in the gait fluctuations commonly observed in healthy populations. Aging which also affects gait complexity, resulting in a loss of adaptability to the surrounding environment, could benefit from gait rehabilitation that incorporates a variable fractal-like stimulus paradigm. Therefore, the present study aimed to investigate the effect of a variable fractal-like visual stimulus on the stride-to-stride fluctuations of older adults during overground walking. Additionally, our study aimed to investigate potential retention effects by instructing the participants to continue walking after turning off the stimulus. Older adults walked 8 min with i) no stimulus (self-paced), ii) a variable fractal-like visual stimulus and iii) an invariant visual stimulus. In the two visual stimuli conditions, the participants walked 8 additional minutes after the stimulus was turned off. Gait complexity was evaluated with the widely used fractal scaling exponent calculated through the detrended fluctuation analysis of the stride time intervals. We found a significant ~20% increase in the scaling exponent from the no stimulus to the variable fractal-like stimulus condition. However, no differences were found when the older adults walked to the invariant stimulus. The observed increase was towards the values found in the past to characterize healthy young adults. We have also observed that these positive effects were retained even when the stimulus was turned off for the fractal condition, practically, acutely restoring gait complexity of older adults. These very promising results should motivate researchers and clinicians to perform clinical trials in order to investigate the potential of visual variable fractal-like stimulus for gait rehabilitation.
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Affiliation(s)
- João R Vaz
- Department of Biomechanics and Center for Research in Human Movement Variability, University of Nebraska at Omaha, Omaha, NE, USA; CIPER, Faculdade de Motricidade Humana, Universidade de Lisboa, Lisbon, Portugal.
| | - Brian A Knarr
- Department of Biomechanics and Center for Research in Human Movement Variability, University of Nebraska at Omaha, Omaha, NE, USA
| | - Nick Stergiou
- Department of Biomechanics and Center for Research in Human Movement Variability, University of Nebraska at Omaha, Omaha, NE, USA; College of Public Health, University of Nebraska Medical Center, Omaha, NE, USA
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Suibkitwanchai K, Sykulski AM, Perez Algorta G, Waller D, Walshe C. Nonparametric time series summary statistics for high-frequency accelerometry data from individuals with advanced dementia. PLoS One 2020; 15:e0239368. [PMID: 32976498 PMCID: PMC7518630 DOI: 10.1371/journal.pone.0239368] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 09/06/2020] [Indexed: 11/18/2022] Open
Abstract
Accelerometry data has been widely used to measure activity and the circadian rhythm of individuals across the health sciences, in particular with people with advanced dementia. Modern accelerometers can record continuous observations on a single individual for several days at a sampling frequency of the order of one hertz. Such rich and lengthy data sets provide new opportunities for statistical insight, but also pose challenges in selecting from a wide range of possible summary statistics, and how the calculation of such statistics should be optimally tuned and implemented. In this paper, we build on existing approaches, as well as propose new summary statistics, and detail how these should be implemented with high frequency accelerometry data. We test and validate our methods on an observed data set from 26 recordings from individuals with advanced dementia and 14 recordings from individuals without dementia. We study four metrics: Interdaily stability (IS), intradaily variability (IV), the scaling exponent from detrended fluctuation analysis (DFA), and a novel nonparametric estimator which we call the proportion of variance (PoV), which calculates the strength of the circadian rhythm using spectral density estimation. We perform a detailed analysis indicating how the time series should be optimally subsampled to calculate IV, and recommend a subsampling rate of approximately 5 minutes for the dataset that has been studied. In addition, we propose the use of the DFA scaling exponent separately for daytime and nighttime, to further separate effects between individuals. We compare the relationships between all these methods and show that they effectively capture different features of the time series.
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Affiliation(s)
- Keerati Suibkitwanchai
- Department of Mathematics and Statistics, Lancaster University, Lancaster, United Kingdom
- * E-mail:
| | - Adam M. Sykulski
- Department of Mathematics and Statistics, Lancaster University, Lancaster, United Kingdom
| | | | - Daniel Waller
- Department of Mathematics and Statistics, Lancaster University, Lancaster, United Kingdom
| | - Catherine Walshe
- Division of Health Research, Lancaster University, Lancaster, United Kingdom
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Kim S, Nam Y, Shin SJ, Park YH, Jeon SG, Kim JI, Kim MJ, Moon M. The Potential Roles of Ghrelin in Metabolic Syndrome and Secondary Symptoms of Alzheimer's Disease. Front Neurosci 2020; 14:583097. [PMID: 33071750 PMCID: PMC7543232 DOI: 10.3389/fnins.2020.583097] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 08/26/2020] [Indexed: 12/12/2022] Open
Abstract
Although the major causative factors of Alzheimer's disease (AD) are the accumulation of amyloid β and hyperphosphorylated tau, AD can also be caused by metabolic dysfunction. The major clinical symptom of AD is cognitive dysfunction. However, AD is also accompanied by various secondary symptoms such as depression, sleep-wake disturbances, and abnormal eating behaviors. Interestingly, the orexigenic hormone ghrelin has been suggested to have beneficial effects on AD-related metabolic syndrome and secondary symptoms. Ghrelin improves lipid distribution and alters insulin sensitivity, effects that are hypothesized to delay the progression of AD. Furthermore, ghrelin can relieve depression by enhancing the secretion of hormones such as serotonin, noradrenaline, and orexin. Moreover, ghrelin can upregulate the expression of neurotrophic factors such as brain-derived neurotrophic factor and modulate the release of proinflammatory cytokines such as tumor necrosis factor α and interleukin 1β. Ghrelin alleviates sleep-wake disturbances by increasing the levels of melatonin, melanin-concentrating hormone. Ghrelin reduces the risk of abnormal eating behaviors by increasing neuropeptide Y and γ-aminobutyric acid. In addition, ghrelin increases food intake by inhibiting fatty acid biosynthesis. However, despite the numerous studies on the role of ghrelin in the AD-related pathology and metabolic disorders, there are only a few studies that investigate the effects of ghrelin on secondary symptoms associated with AD. In this mini review, our purpose is to provide the insights of future study by organizing the previous studies for the role of ghrelin in AD-related pathology and metabolic disorders.
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Affiliation(s)
- Sujin Kim
- Department of Biochemistry, College of Medicine, Konyang University, Daejeon, South Korea
| | - Yunkwon Nam
- Department of Biochemistry, College of Medicine, Konyang University, Daejeon, South Korea
| | - Soo Jung Shin
- Department of Biochemistry, College of Medicine, Konyang University, Daejeon, South Korea
| | - Yong Ho Park
- Department of Biochemistry, College of Medicine, Konyang University, Daejeon, South Korea
| | - Seong Gak Jeon
- Department of Biochemistry, College of Medicine, Konyang University, Daejeon, South Korea.,Department of Neural Development and Disease, Korea Brain Research Institute (KBRI), Daegu, South Korea
| | - Jin-Il Kim
- Department of Nursing, College of Nursing, Jeju National University, Jeju-si, South Korea
| | - Min-Jeong Kim
- Department of Biochemistry, College of Medicine, Konyang University, Daejeon, South Korea
| | - Minho Moon
- Department of Biochemistry, College of Medicine, Konyang University, Daejeon, South Korea
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21
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Li P, Lim ASP, Gao L, Hu C, Yu L, Bennett DA, Buchman AS, Hu K. More random motor activity fluctuations predict incident frailty, disability, and mortality. Sci Transl Med 2020; 11:11/516/eaax1977. [PMID: 31666398 DOI: 10.1126/scitranslmed.aax1977] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 09/20/2019] [Indexed: 12/11/2022]
Abstract
Mobile healthcare increasingly relies on analytical tools that can extract meaningful information from ambulatory physiological recordings. We tested whether a nonlinear tool of fractal physiology could predict long-term health consequences in a large, elderly cohort. Fractal physiology is an emerging field that aims to study how fractal temporal structures in physiological fluctuations generated by complex physiological networks can provide important information about system adaptability. We assessed fractal temporal correlations in the spontaneous fluctuations of ambulatory motor activity of 1275 older participants at baseline, with a follow-up period of up to 13 years. We found that people with reduced temporal correlations (more random activity fluctuations) at baseline had increased risk of frailty, disability, and all-cause death during follow-up. Specifically, for 1-SD decrease in the temporal activity correlations of this studied cohort, the risk of frailty increased by 31%, the risk of disability increased by 15 to 25%, and the risk of death increased by 26%. These incidences occurred on average 4.7 years (frailty), 3 to 4.2 years (disability), and 5.8 years (death) after baseline. These observations were independent of age, sex, education, chronic health conditions, depressive symptoms, cognition, motor function, and total daily activity. The temporal structures in daily motor activity fluctuations may contain unique prognostic information regarding wellness and health in the elderly population.
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Affiliation(s)
- Peng Li
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA. .,Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Andrew S P Lim
- Division of Neurology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON M4N 3M5, Canada
| | - Lei Gao
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA.,Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Chelsea Hu
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Lei Yu
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL 60612, USA
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL 60612, USA
| | - Aron S Buchman
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL 60612, USA
| | - Kun Hu
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA. .,Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA
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22
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Raichlen DA, Klimentidis YC, Hsu CH, Alexander GE. Fractal Complexity of Daily Physical Activity Patterns Differs With Age Over the Life Span and Is Associated With Mortality in Older Adults. J Gerontol A Biol Sci Med Sci 2020; 74:1461-1467. [PMID: 30371743 DOI: 10.1093/gerona/gly247] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Accelerometers are included in a wide range of devices that monitor and track physical activity for health-related applications. However, the clinical utility of the information embedded in their rich time-series data has been greatly understudied and has yet to be fully realized. Here, we examine the potential for fractal complexity of actigraphy data to serve as a clinical biomarker for mortality risk. METHODS We use detrended fluctuation analysis (DFA) to analyze actigraphy data from the National Health and Nutrition Examination Survey (NHANES; n = 11,694). The DFA method measures fractal complexity (signal self-affinity across time-scales) as correlations between the amplitude of signal fluctuations in time-series data across a range of time-scales. The slope, α, relating the fluctuation amplitudes to the time-scales over which they were measured describes the complexity of the signal. RESULTS Fractal complexity of physical activity (α) decreased significantly with age (p = 1.29E-6) and was lower in women compared with men (p = 1.79E-4). Higher levels of moderate-to-vigorous physical activity in older adults and in women were associated with greater fractal complexity. In adults aged 50-79 years, lower fractal complexity of activity (α) was associated with greater mortality (hazard ratio = 0.64; 95% confidence interval = 0.49-0.82) after adjusting for age, exercise engagement, chronic diseases, and other covariates associated with mortality. CONCLUSIONS Wearable accelerometers can provide a noninvasive biomarker of physiological aging and mortality risk after adjusting for other factors strongly associated with mortality. Thus, this fractal analysis of accelerometer signals provides a novel clinical application for wearable accelerometers, advancing efforts for remote monitoring of physiological health by clinicians.
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Affiliation(s)
- David A Raichlen
- School of Anthropology, Mel and Enid Zuckerman College of Public Health, Tucson
| | - Yann C Klimentidis
- Department of Epidemiology and Biostatistics, Mel and Enid Zuckerman College of Public Health, Tucson
- BIO5 Institute, University of Arizona, Tucson
| | - Chiu-Hsieh Hsu
- Department of Epidemiology and Biostatistics, Mel and Enid Zuckerman College of Public Health, Tucson
| | - Gene E Alexander
- BIO5 Institute, University of Arizona, Tucson
- Departments of Psychology and Psychiatry
- Evelyn F. McKnight Brain Institute
- Neuroscience Graduate Interdisciplinary Program
- Physiological Sciences Graduate Interdisciplinary Program
- Arizona Alzheimer's Consortium, Phoenix
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Canazei M, Turiaux J, Huber SE, Marksteiner J, Papousek I, Weiss EM. Actigraphy for Assessing Light Effects on Sleep and Circadian Activity Rhythm in Alzheimer's Dementia: A Narrative Review. Curr Alzheimer Res 2020; 16:1084-1107. [DOI: 10.2174/1567205016666191010124011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 08/10/2019] [Accepted: 09/08/2019] [Indexed: 12/18/2022]
Abstract
Background:
Alzheimer's Disease (AD) is often accompanied by severe sleep problems and
circadian rhythm disturbances which may to some extent be attributed to a dysfunction in the biological
clock. The 24-h light/dark cycle is the strongest Zeitgeber for the biological clock. People with AD,
however, often live in environments with inappropriate photic Zeitgebers. Timed bright light exposure
may help to consolidate sleep- and circadian rest/activity rhythm problems in AD, and may be a low-risk
alternative to pharmacological treatment.
Objective & Method:
In the present review, experts from several research disciplines summarized the
results of twenty-seven light intervention studies which used wrist actigraphy to measure sleep and circadian
activity in AD patients.
Results:
Taken together, the findings remain inconclusive with regard to beneficial light effects. However,
the considered studies varied substantially with respect to the utilized light intervention, study design,
and usage of actigraphy. The paper provides a comprehensive critical discussion of these issues.
Conclusion:
Fusing knowledge across complementary research disciplines has the potential to critically
advance our understanding of the biological input of light on health and may contribute to architectural
lighting designs in hospitals, as well as our homes and work environments.
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Affiliation(s)
- Markus Canazei
- Research Department, Bartenbach LichtLabor GmbH Ringgold Standard Institution, Bartenbach GmbH, Rinnerstrasse 14, Aldrans 6071, Austria
| | - Julian Turiaux
- Department of Psychology, University of Graz, Graz, Austria
| | - Stefan E. Huber
- Institute of Ion Physics and Applied Physics, University of Innsbruck, Innsbruck, Tirol, Austria
| | - Josef Marksteiner
- Department of Psychiatry and Psychotherapy A, General Hospital, Milserstrasse 10 , Hall Tirol 6060, Austria
| | - Ilona Papousek
- Department of Psychology, University of Graz, Graz, Austria
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Li P, Yu L, Yang J, Lo MT, Hu C, Buchman AS, Bennett DA, Hu K. Interaction between the progression of Alzheimer's disease and fractal degradation. Neurobiol Aging 2019; 83:21-30. [PMID: 31585364 PMCID: PMC6858962 DOI: 10.1016/j.neurobiolaging.2019.08.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 08/22/2019] [Accepted: 08/24/2019] [Indexed: 01/08/2023]
Abstract
Many outputs from healthy neurophysiological systems including motor activity display nonrandom fluctuations with fractal scaling behavior as characterized by similar temporal fluctuation patterns across a range of time scales. Degraded fractal regulation predicts adverse consequences including Alzheimer's dementia. We examined longitudinal changes in the scaling behavior of motor activity fluctuations during the progression of Alzheimer's disease (AD) in 1068 participants in the Rush Memory and Aging Project. Motor activity of up to 10 days was recorded annually for up to 13 years. Cognitive assessments and clinical diagnoses were administered annually in the same participants. We found that fractal regulation gradually degraded over time (p < 0.0001) even during the stage with no cognitive impairment. The degradation rate was more than doubled after the diagnosis of mild cognitive impairment and more than doubled further after the diagnosis of Alzheimer's dementia (p's ≤ 0.0005). Besides, the longitudinal degradation of fractal regulation significantly correlated with the decline in cognitive performance throughout the progression from no cognitive impairment to mild cognitive impairment, and to AD (p < 0.001). All effects remained the same in subsequent sensitivity analyses that included only 255 decedents with autopsy-confirmed Alzheimer's pathology. These results indicate that the progression of AD accelerates fractal degradation and that fractal degradation may be an integral part of the process of AD.
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Affiliation(s)
- Peng Li
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA; Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA, USA.
| | - Lei Yu
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Jingyun Yang
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Men-Tzung Lo
- Institute of Translational and Interdisciplinary Medicine and Department of Biomedical Sciences and Engineering, National Central University, Taoyuan, Taiwan
| | - Chelsea Hu
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA
| | - Aron S Buchman
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Kun Hu
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA; Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA, USA.
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25
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Huber SE, Sachse P, Mauracher A, Marksteiner J, Pohl W, Weiss EM, Canazei M. Assessment of Fractal Characteristics of Locomotor Activity of Geriatric In-Patients With Alzheimer's Dementia. Front Aging Neurosci 2019; 11:272. [PMID: 31636559 PMCID: PMC6787148 DOI: 10.3389/fnagi.2019.00272] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 09/19/2019] [Indexed: 11/24/2022] Open
Abstract
INTRODUCTION Many physiological signals yield fractal characteristics, i.e., finer details at higher magnifications resemble details of the whole. Evidence has been accumulating that such fractal scaling is basically a consequence of interaction-dominant feedback mechanisms that cooperatively generate those signals. Neurodegenerative diseases provide a natural framework to evaluate this paradigm when this cooperative function declines. However, methodological issues need to be cautiously taken into account in order to be able to provide reliable as well as valid interpretations of such signal analyses. METHODS Two conceptually different fractal analyses, i.e., detrended fluctuation analysis (DFA) and analysis of cumulative distributions of durations (CDDs), are applied to actigraphy data of 36 geriatric in-patients diagnosed with dementia. The impact of the used time resolution for data acquisition on the assessed fractal outcome parameters is particularly investigated. Moreover, associations between these parameters and scores from the Mini-Mental-State-Examination and circadian activity parameters are explored. RESULTS Both analyses yield significant deviations from (mono-)fractal scaling over the entire considered time range. DFA provides robust measures for the observed break-down of fractal scaling. In contrast, analysis of CDDs results in measures which highly fluctuate with respect to the time resolution of the assessed data which affects also further derived quantities such as scaling exponents or associations with other (clinically relevant) assessed parameters. DISCUSSION To scrutinize actigraphic signal characteristics and especially their (deviations from) fractal scaling may be a useful tool for aiding diagnosis, characterization, and monitoring of dementia. However, results may, besides contextual aspects, also substantially depend on specific methodological choices. In order to arrive at both reliable and valid interpretations, these complications need to be carefully elaborated in future research.
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Affiliation(s)
- Stefan E. Huber
- Institute of Ion Physics and Applied Physics, University of Innsbruck, Innsbruck, Austria
- Department of Psychology, University of Innsbruck, Innsbruck, Austria
- Bartenbach GmbH, Aldrans, Austria
| | - Pierre Sachse
- Department of Psychology, University of Innsbruck, Innsbruck, Austria
| | - Andreas Mauracher
- Institute of Ion Physics and Applied Physics, University of Innsbruck, Innsbruck, Austria
| | - Josef Marksteiner
- Department of Psychiatry and Psychotherapy A, State Hospital Hall, Hall in Tirol, Austria
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26
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Hodges EL, Ashpole NM. Aging circadian rhythms and cannabinoids. Neurobiol Aging 2019; 79:110-118. [PMID: 31035036 DOI: 10.1016/j.neurobiolaging.2019.03.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 03/11/2019] [Accepted: 03/17/2019] [Indexed: 01/04/2023]
Abstract
Numerous aspects of mammalian physiology exhibit cyclic daily patterns known as circadian rhythms. However, studies in aged humans and animals indicate that these physiological rhythms are not consistent throughout the life span. The simultaneous development of disrupted circadian rhythms and age-related impairments suggests a shared mechanism, which may be amenable to therapeutic intervention. Recently, the endocannabinoid system has emerged as a complex signaling network, which regulates numerous aspects of circadian physiology relevant to the neurobiology of aging. Agonists of cannabinoid receptor-1 (CB1) have consistently been shown to decrease neuronal activity, core body temperature, locomotion, and cognitive function. Paradoxically, several lines of evidence now suggest that very low doses of cannabinoids are beneficial in advanced age. One potential explanation for this phenomenon is that these drugs exhibit hormesis-a biphasic dose-response wherein low doses produce the opposite effects of higher doses. Therefore, it is important to determine the dose-, age-, and time-dependent effects of these substances on the regulation of circadian rhythms and other processes dysregulated in aging. This review highlights 3 fields-biological aging, circadian rhythms, and endocannabinoid signaling-to critically assess the therapeutic potential of endocannabinoid modulation in aged individuals. If the hormetic properties of exogenous cannabinoids are confirmed, we conclude that precise administration of these compounds may bidirectionally entrain central and peripheral circadian clocks and benefit multiple aspects of aging physiology.
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Affiliation(s)
- Erik L Hodges
- Pharmacology Division, Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, Oxford, MS, USA
| | - Nicole M Ashpole
- Pharmacology Division, Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, Oxford, MS, USA.
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Aguilar-Velázquez D, Guzmán-Vargas L. Critical synchronization and 1/f noise in inhibitory/excitatory rich-club neural networks. Sci Rep 2019; 9:1258. [PMID: 30718817 PMCID: PMC6361933 DOI: 10.1038/s41598-018-37920-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 12/17/2018] [Indexed: 12/16/2022] Open
Abstract
In recent years, diverse studies have reported that different brain regions, which are internally densely connected, are also highly connected to each other. This configuration seems to play a key role in integrating and interchanging information between brain areas. Also, changes in the rich-club connectivity and the shift from inhibitory to excitatory behavior of hub neurons have been associated with several diseases. However, there is not a clear understanding about the role of the proportion of inhibitory/excitatory hub neurons, the dynamic consequences of rich-club disconnection, and hub inhibitory/excitatory shifts. Here, we study the synchronization and temporal correlations in the neural Izhikevich model, which comprises excitatory and inhibitory neurons located in a scale-free hierarchical network with rich-club connectivity. We evaluated the temporal autocorrelations and global synchronization dynamics displayed by the system in terms of rich-club connectivity and hub inhibitory/excitatory population. We evaluated the synchrony between pairs of sets of neurons by means of the global lability synchronization, based on the rate of change in the total number of synchronized signals. The results show that for a wide range of excitatory/inhibitory hub ratios the network displays 1/f dynamics with critical synchronization that is concordant with numerous health brain registers, while a network configuration with a vast majority of excitatory hubs mostly exhibits short-term autocorrelations with numerous large avalanches. Furthermore, rich-club connectivity promotes the increase of the global lability of synchrony and the temporal persistence of the system.
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Affiliation(s)
- Daniel Aguilar-Velázquez
- Unidad Profesional Interdisciplinaria en Ingeniería y Tecnologías Avanzadas, Instituto Politécnico Nacional, Av. IPN No. 2580, L. Ticomán, Ciudad de México, 07340, Mexico
| | - Lev Guzmán-Vargas
- Unidad Profesional Interdisciplinaria en Ingeniería y Tecnologías Avanzadas, Instituto Politécnico Nacional, Av. IPN No. 2580, L. Ticomán, Ciudad de México, 07340, Mexico.
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28
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Chen XY, Du YF, Chen L. Neuropeptides Exert Neuroprotective Effects in Alzheimer's Disease. Front Mol Neurosci 2019; 11:493. [PMID: 30687008 PMCID: PMC6336706 DOI: 10.3389/fnmol.2018.00493] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 12/21/2018] [Indexed: 01/03/2023] Open
Abstract
Alzheimer's disease (AD) is an age-related neurodegenerative disorder characterized by cognitive deficits and neuronal loss. Deposition of beta-amyloid peptide (Aβ) causes neurotoxicity through the formation of plaques in brains of Alzheimer's disease. Numerous studies have indicated that the neuropeptides including ghrelin, neurotensin, pituitary adenylate cyclase-activating polypeptide (PACAP), neuropeptide Y, substance P and orexin are closely related to the pathophysiology of Alzheimer's disease. The levels of neuropeptides and their receptors change in Alzheimer's disease. These neuropeptides exert neuroprotective roles mainly through preventing Aβ accumulation, increasing neuronal glucose transport, increasing the production of neurotrophins, inhibiting endoplasmic reticulum stress and autophagy, modulating potassium channel activity and hippocampal long-term potentiation. Therefore, the neuropeptides may function as potential drug targets in the prevention and cure of Alzheimer's disease.
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Affiliation(s)
- Xin-Yi Chen
- Department of Physiology and Pathophysiology, Qingdao University, Qingdao, China.,Department of Neurology, Provincial Hospital Affiliated to Shandong University, Jinan, China
| | - Yi-Feng Du
- Department of Neurology, Provincial Hospital Affiliated to Shandong University, Jinan, China
| | - Lei Chen
- Department of Physiology and Pathophysiology, Qingdao University, Qingdao, China
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Hiller AJ, Ishii M. Disorders of Body Weight, Sleep and Circadian Rhythm as Manifestations of Hypothalamic Dysfunction in Alzheimer's Disease. Front Cell Neurosci 2018; 12:471. [PMID: 30568576 PMCID: PMC6289975 DOI: 10.3389/fncel.2018.00471] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 11/19/2018] [Indexed: 12/31/2022] Open
Abstract
While cognitive decline and memory loss are the major clinical manifestations of Alzheimer’s disease (AD), they are now recognized as late features of the disease. Recent failures in clinical drug trials highlight the importance of evaluating and treating patients with AD as early as possible and the difficulties in developing effective therapies once the disease progresses. Since the pathological hallmarks of AD including the abnormal aggregation of amyloid-beta (Aβ) and tau can occur decades before any significant cognitive decline in the preclinical stage of AD, it is important to identify the earliest clinical manifestations of AD and elucidate their underlying cellular and molecular mechanisms. Importantly, metabolic and non-cognitive manifestations of AD such as weight loss and alterations of peripheral metabolic signals can occur before the onset of cognitive symptoms and worsen with disease progression. Accumulating evidence suggests that the major culprit behind these early metabolic and non-cognitive manifestations of AD is AD pathology causing dysfunction of the hypothalamus, a brain region critical for integrating peripheral signals with essential homeostatic physiological functions. Here, we aim to highlight recent developments that address the role of AD pathology in the development of hypothalamic dysfunction associated with metabolic and non-cognitive manifestations seen in AD. Understanding the mechanisms underlying hypothalamic dysfunction in AD could give key new insights into the development of novel biomarkers and therapeutic targets.
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Affiliation(s)
- Abigail J Hiller
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, Cornell University, New York, NY, United States
| | - Makoto Ishii
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, Cornell University, New York, NY, United States.,Department of Neurology, Weill Cornell Medicine, Cornell University, New York, NY, United States
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Abstract
PURPOSE OF REVIEW The endogenous circadian rhythms are one of the cardinal processes that control sleep. They are self-sustaining biological rhythms with a periodicity of approximately 24 hours that may be entrained by external zeitgebers (German for time givers), such as light, exercise, and meal times. This article discusses the physiology of the circadian rhythms, their relationship to neurologic disease, and the presentation and treatment of circadian rhythm sleep-wake disorders. RECENT FINDINGS Classic examples of circadian rhythms include cortisol and melatonin secretion, body temperature, and urine volume. More recently, the impact of circadian rhythm on several neurologic disorders has been investigated, such as the timing of occurrence of epileptic seizures as well as neurobehavioral functioning in dementia. Further updates include a more in-depth understanding of the symptoms, consequences, and treatment of circadian sleep-wake disorders, which may occur because of extrinsic misalignment with clock time or because of intrinsic dysfunction of the brain. An example of extrinsic misalignment occurs with jet lag during transmeridian travel or with intrinsic circadian rhythm sleep-wake disorders such as advanced or delayed sleep-wake phase disorders. In advanced sleep-wake phase disorder, which is most common in elderly individuals, sleep onset and morning arousal are undesirably early, leading to impaired evening function with excessive sleepiness and sleep-maintenance insomnia with early morning awakening. By contrast, delayed sleep-wake phase disorder is characterized by an inability to initiate sleep before the early morning hours, with subsequent delayed rise time, leading to clinical symptoms of severe sleep-onset insomnia coupled with excessive daytime sleepiness in the morning hours, as patients are unable to "sleep in" to attain sufficient sleep quantity. Irregular sleep-wake rhythm disorder is misentrainment with patches of brief sleep and wakefulness spread throughout the day, leading to unstable sleep and waking behavioral patterns and an entirely idiosyncratic sleep-wake schedule. SUMMARY Familiarity with these major circadian rhythm sleep-wake disorder phenotypes and their overlap with other neurologic disorders is essential for the neurologist so that clinicians may intervene and improve patient functioning and quality of life.
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Li P, Yu L, Lim ASP, Buchman AS, Scheer FAJL, Shea SA, Schneider JA, Bennett DA, Hu K. Fractal regulation and incident Alzheimer's disease in elderly individuals. Alzheimers Dement 2018; 14:1114-1125. [PMID: 29733807 PMCID: PMC6201319 DOI: 10.1016/j.jalz.2018.03.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 03/13/2018] [Accepted: 03/21/2018] [Indexed: 01/01/2023]
Abstract
Introduction: Healthy physiological systems exhibit fractal regulation (FR), generating similar fluctuation patterns in physiological outputs across different time scales. FR in motor activity is degraded in dementia, and the degradation correlates to cognitive decline. We tested whether degraded FR predicts Alzheimer’s dementia. Methods: FR in motor activity was assessed in 1097 nondemented older adults at baseline. Cognition was assessed annually for up to 11 years. Results: Participants with an FR metric at the 10th percentile in this cohort had a 1.8-fold Alzheimer’s disease risk (equivalent to the effect of being ~5.2 years older) and 1.3-fold risk for mild cognitive impairment (equivalent to the effect of being ~3.0 years older) than those at the 90th percentile. Consistently, degraded FR predicted faster cognitive decline. These associations were independent of physical activity, sleep fragmentation, and stability of daily activity rhythms. Discussion: FR may be a useful tool for predicting Alzheimer’s dementia.
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Affiliation(s)
- Peng Li
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA; Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA, USA.
| | - Lei Yu
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Andrew S P Lim
- Division of Neurology, Department of Medicine, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - Aron S Buchman
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Frank A J L Scheer
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA; Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Steven A Shea
- Oregon Institute of Occupational Health Sciences, Oregon Health and Science University, Portland, OR, USA
| | - Julie A Schneider
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA
| | - Kun Hu
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA; Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA, USA.
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Joustra SD, Gu C, Rohling JHT, Pickering L, Klose M, Hu K, Scheer FA, Feldt-Rasmussen U, Jennum PJ, Pereira AM, Biermasz NR, Meijer JH. Decrease in scale invariance of activity fluctuations with aging and in patients with suprasellar tumors. Chronobiol Int 2017; 35:368-377. [PMID: 29182371 PMCID: PMC5862770 DOI: 10.1080/07420528.2017.1407779] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Motor activity in healthy young humans displays intrinsic fluctuations that are scale-invariant over a wide range of time scales (from minutes to hours). Human postmortem and animal lesion studies showed that the intact function of the suprachiasmatic nucleus (SCN) is required to maintain such scale-invariant patterns. We therefore hypothesized that scale invariance is degraded in patients treated for suprasellar tumors that compress the SCN. To test the hypothesis, we investigated 68 patients with nonfunctioning pituitary macroadenoma and 22 patients with craniopharyngioma, as well as 72 age-matched healthy controls (age range 21.0–70.6 years). Spontaneous wrist locomotor activity was measured for 7 days with actigraphy, and detrended fluctuation analysis was applied to assess correlations over a range of time scales from minutes to 24 h. For all the subjects, complex scale-invariant correlations were only present for time scales smaller than 1.5 h, and became more random at time scales 1.5–10 h. Patients with suprasellar tumors showed a larger decrease in correlations at 1.5–10 h as compared to healthy controls. Within healthy subject, gender and age >33 year were associated with attenuated scale invariance. Conversely, activity patterns at time scales between 10 and 24 h were significantly more regular than all other time scales, and this was mostly associated with age. In conclusion, scale invariance is degraded in healthy subjects at the ages of >33 year as characterized by attenuation of correlations at time scales 1.5–10 h. In addition, scale invariance was more degraded in patients with suprasellar tumors as compared to healthy subjects.
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Affiliation(s)
- S D Joustra
- a Center for Endocrine Tumors Leiden, Department of Medicine, Division of Endocrinology , Leiden University Medical Center , Leiden , The Netherlands
| | - C Gu
- b Department of Molecular Cell Biology , Laboratory for Neurophysiology, Leiden University Medical Center , Leiden , The Netherlands.,c Business School , University of Shanghai for Science and Technology , Shanghai , China
| | - J H T Rohling
- b Department of Molecular Cell Biology , Laboratory for Neurophysiology, Leiden University Medical Center , Leiden , The Netherlands
| | - L Pickering
- d Department of Medical Endocrinology , Rigshospitalet, Copenhagen University Hospital , Copenhagen , Denmark.,e Danish Center for Sleep Medicine , Neurophysiologic Clinic, Rigshospitalet, Copenhagen University Hospital , Copenhagen , Denmark
| | - M Klose
- d Department of Medical Endocrinology , Rigshospitalet, Copenhagen University Hospital , Copenhagen , Denmark
| | - K Hu
- f Division of Sleep and Circadian Disorders , Brigham and Women's Hospital , Boston , MA , USA.,g Division of Sleep Medicine , Harvard Medical School , Boston , MA , USA
| | - F A Scheer
- f Division of Sleep and Circadian Disorders , Brigham and Women's Hospital , Boston , MA , USA.,g Division of Sleep Medicine , Harvard Medical School , Boston , MA , USA
| | - U Feldt-Rasmussen
- d Department of Medical Endocrinology , Rigshospitalet, Copenhagen University Hospital , Copenhagen , Denmark
| | - P J Jennum
- e Danish Center for Sleep Medicine , Neurophysiologic Clinic, Rigshospitalet, Copenhagen University Hospital , Copenhagen , Denmark
| | - A M Pereira
- a Center for Endocrine Tumors Leiden, Department of Medicine, Division of Endocrinology , Leiden University Medical Center , Leiden , The Netherlands
| | - N R Biermasz
- a Center for Endocrine Tumors Leiden, Department of Medicine, Division of Endocrinology , Leiden University Medical Center , Leiden , The Netherlands
| | - J H Meijer
- b Department of Molecular Cell Biology , Laboratory for Neurophysiology, Leiden University Medical Center , Leiden , The Netherlands
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Li P, Morris CJ, Patxot M, Yugay T, Mistretta J, Purvis TE, Scheer FAJL, Hu K. Reduced Tolerance to Night Shift in Chronic Shift Workers: Insight From Fractal Regulation. Sleep 2017; 40:3836914. [PMID: 28838129 PMCID: PMC6317507 DOI: 10.1093/sleep/zsx092] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Study Objectives Healthy physiology is characterized by fractal regulation (FR) that generates similar structures in the fluctuations of physiological outputs at different time scales. Perturbed FR is associated with aging and age-related pathological conditions. Shift work, involving repeated and chronic exposure to misaligned environmental and behavioral cycles, disrupts circadian coordination. We tested whether night shifts perturb FR in motor activity and whether night shifts affect FR in chronic shift workers and non-shift workers differently. Methods We studied 13 chronic shift workers and 14 non-shift workers as controls using both field and in-laboratory experiments. In the in-laboratory study, simulated night shifts were used to induce a misalignment between the endogenous circadian pacemaker and the sleep-wake cycles (ie, circadian misalignment) while environmental conditions and food intake were controlled. Results In the field study, we found that FR was robust in controls but broke down in shift workers during night shifts, leading to more random activity fluctuations as observed in patients with dementia. The night shift effect was present even 2 days after ending night shifts. The in-laboratory study confirmed that night shifts perturbed FR in chronic shift workers and showed that FR in controls was more resilience to the circadian misalignment. Moreover, FR during real and simulated night shifts was more perturbed in those who started shift work at older ages. Conclusions Chronic shift work causes night shift intolerance, which is probably linked to the degraded plasticity of the circadian control system.
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Affiliation(s)
- Peng Li
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA
| | - Christopher J Morris
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA
| | - Melissa Patxot
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA
| | - Tatiana Yugay
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA
| | - Joseph Mistretta
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA
| | - Taylor E Purvis
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA
| | - Frank A J L Scheer
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA
| | - Kun Hu
- Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA
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Figueiro MG. Light, sleep and circadian rhythms in older adults with Alzheimer's disease and related dementias. Neurodegener Dis Manag 2017; 7:119-145. [PMID: 28534696 PMCID: PMC5836917 DOI: 10.2217/nmt-2016-0060] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 01/11/2017] [Indexed: 02/04/2023] Open
Abstract
Alzheimer's disease and related dementias (ADRD) can cause sleep and behavioral problems that are problematic for ADRD patients and their family caregivers. Light therapy has shown promise as a nonpharmacological treatment, and preliminary studies demonstrate that timed light exposure can consolidate and improve nighttime sleep efficiency, increase daytime wakefulness and reduce evening agitation without the adverse effects of pharmacological solutions. Compliance with light treatment and the accurate measurement of light exposures during treatment, however, have presented barriers for the adoption of light therapy for ADRD. Recent research showing that the circadian system is maximally sensitive to short-wavelength light opens the way for the potential application of lower, more-targeted light intensities to maximize compliance and individualize light dose/timing in therapeutic settings.
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Affiliation(s)
- Mariana G Figueiro
- Lighting Research Center, Rensselaer Polytechnic Institute, 21 Union Street, Troy, NY 12180, USA
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Li P, To T, Chiang WY, Escobar C, Buijs RM, Hu K. Fractal Regulation in Temporal Activity Fluctuations: A Biomarker for Circadian Control and Beyond. JSM BIOMARKERS 2017; 3:1008. [PMID: 28553673 PMCID: PMC5443249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Motor activity in humans and other animals possesses fractal temporal fluctuations that co-exists with circadian or daily activity rhythms. The perturbations in fractal activity patterns are often accompanied by altered circadian/daily rhythms. The goal of this study is to test whether fractal regulation in motor activity provides physiological information independent from 24-h/circadian rhythmicity. To achieve the goal, we studied locomotor activity recordings of rats with the lesion of the suprachiasmatic nucleus (SCN) that are known to have diminished circadian/daily activity rhythms and perturbed fractal regulation. By restricting feeding time (i.e., food was only availability in the dark period of the 12h: 12h light-dark cycles), we found that mean activity levels in these animals displayed significant 24-h rhythms. In contrast, the restricted feeding had no influences on the perturbed fractal regulation in these SCN-lesioned animals, i.e., activity fluctuations in these animals remained random over a wide range of time scales from 2-20h. Our results indicate that 24-h rhythm of food availability can restore/improve circadian/daily rhythms in the SCN-lesioned animals but not necessarily improve the disrupted fractal activity regulation in these animals. This study provides clear and direct evidence that fractal activity patterns offer complementary information about motor activity regulation at multiple time scales that is beyond 24-h rhythm control.
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Affiliation(s)
- Peng Li
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, United States
- Division of Sleep Medicine, Harvard Medical School, United States
- School of Control Science and Engineering, Shandong University, China
| | - Tommy To
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, United States
| | - Wei-Yin Chiang
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, United States
- Division of Sleep Medicine, Harvard Medical School, United States
| | - Carolina Escobar
- Departamento de Anatomía, Facultad de Medicina, Edificio “B” 4° Piso, Universidad Nacional Autónoma de México, Mexico
| | - Ruud M Buijs
- Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico
| | - Kun Hu
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, United States
- Division of Sleep Medicine, Harvard Medical School, United States
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Probing the Fractal Pattern of Heartbeats in Drosophila Pupae by Visible Optical Recording System. Sci Rep 2016; 6:31950. [PMID: 27535299 PMCID: PMC4989149 DOI: 10.1038/srep31950] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 08/01/2016] [Indexed: 11/10/2022] Open
Abstract
Judiciously tuning heart rates is critical for regular cardiovascular function. The fractal pattern of heartbeats — a multiscale regulation in instantaneous fluctuations — is well known for vertebrates. The most primitive heart system of the Drosophila provides a useful model to understand the evolutional origin of such a fractal pattern as well as the alterations of fractal pattern during diseased statuses. We developed a non-invasive visible optical heart rate recording system especially suitable for long-term recording by using principal component analysis (PCA) instead of fluorescence recording system to avoid the confounding effect from intense light irradiation. To deplete intracellular Ca2+ levels, the expression of sarco-endoplasmic reticulum Ca2+-ATPase (SERCA) was tissue-specifically knocked down. The SERCA group shows longer heart beat intervals (Mean ± SD: 1009.7 ± 151.6 ms) as compared to the control group (545.5 ± 45.4 ms, p < 0.001). The multiscale correlation of SERCA group (scaling exponent: 0.77 ± 0.07), on the other hand, is weaker than that of the control Drosophila (scaling exponent: 0.85 ± 0.03) (p = 0.016).
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Yeh CH, Lo MT, Hu K. Spurious cross-frequency amplitude-amplitude coupling in nonstationary, nonlinear signals. PHYSICA A 2016; 454:143-150. [PMID: 27103757 PMCID: PMC4834901 DOI: 10.1016/j.physa.2016.02.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Recent studies of brain activities show that cross-frequency coupling (CFC) play an important role in memory and learning. Many measures have been proposed to investigate the CFC phenomenon, including the correlation between the amplitude envelopes of two brain waves at different frequencies - cross-frequency amplitude-amplitude coupling (AAC). In this short communication, we describe how nonstationary, nonlinear oscillatory signals may produce spurious cross-frequency AAC. Utilizing the empirical mode decomposition, we also propose a new method for assessment of AAC that can potentially reduce the effects of nonlinearity and nonstatonarity and, thus, help to avoid the detection of artificial AACs. We compare the performances of this new method and the traditional Fourier-based AAC method. We also discuss the strategies to identify potential spurious AACs.
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Affiliation(s)
- Chien-Hung Yeh
- Department of Electrical Engineering, National Central University, Taoyuan City 32001, Taiwan
- Research Center for Adaptive Data Analysis, National Central University, Taoyuan City 32001, Taiwan
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, 221 Longwood Avenue, Boston, MA 02115, USA
| | - Men-Tzung Lo
- Research Center for Adaptive Data Analysis, National Central University, Taoyuan City 32001, Taiwan
- Institute of Translational and Interdisciplinary Medicine and Department of Biomedical Sciences and Engineering, National Central University, Taoyuan City 32001, Taiwan
- Correspondence to: Institute of Translational and Interdisciplinary Medicine and Department of Biomedical Sciences and Engineering, National Central University, Taoyuan City 32001, Taiwan. Tel.: +886 3 422 7151 #27756. (M.-T. Lo)., Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, 221 Longwood Avenue, Boston, MA 02115, USA. Tel.: +1 617 525 8694. (K. Hu)
| | - Kun Hu
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, 221 Longwood Avenue, Boston, MA 02115, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA
- Correspondence to: Institute of Translational and Interdisciplinary Medicine and Department of Biomedical Sciences and Engineering, National Central University, Taoyuan City 32001, Taiwan. Tel.: +886 3 422 7151 #27756. (M.-T. Lo)., Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, 221 Longwood Avenue, Boston, MA 02115, USA. Tel.: +1 617 525 8694. (K. Hu)
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Hu K, Riemersma - van der Lek RF, Patxot M, Li P, Shea SA, Scheer FAJL, Van Someren EJW. Progression of Dementia Assessed by Temporal Correlations of Physical Activity: Results From a 3.5-Year, Longitudinal Randomized Controlled Trial. Sci Rep 2016; 6:27742. [PMID: 27292543 PMCID: PMC4904193 DOI: 10.1038/srep27742] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 05/19/2016] [Indexed: 01/04/2023] Open
Abstract
Cross-sectional studies show that activity fluctuations in healthy young adults possess robust temporal correlations that become altered with aging, and in dementia and depression. This study was designed to test whether or not within-subject changes of activity correlations (i) track the clinical progression of dementia, (ii) reflect the alterations of depression symptoms in patients with dementia, and (iii) can be manipulated by clinical interventions aimed at stabilizing circadian rhythmicity and improving sleep in dementia, namely timed bright light therapy and melatonin supplementation. We examined 144 patients with dementia (70-96 years old) who were assigned to daily treatment with bright light, bedtime melatonin, both or placebos only in a 3.5-year double-blinded randomized clinical trial. We found that activity correlations at temporal scales <~2 hours significantly decreased over time and that light treatment attenuated the decrease by ~73%. Moreover, the decrease of temporal activity correlations positively correlated with the degrees of cognitive decline and worsening of mood though the associations were relatively weak. These results suggest a mechanistic link between multiscale activity regulation and circadian/sleep function in dementia patients. Whether temporal activity patterns allow unobtrusive, long-term monitoring of dementia progression and mood changes is worth further investigation.
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Affiliation(s)
- Kun Hu
- Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital; and Division of Sleep Medicine, Harvard Medical School, Boston, MA 02215, United States
| | - Rixt F. Riemersma - van der Lek
- Netherlands Institute for Neuroscience, Amsterdam, The Netherlands
- University of Groningen, University Medical Center Groningen, Department of Psychiatry, Groningen, The Netherlands
| | - Melissa Patxot
- Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital; and Division of Sleep Medicine, Harvard Medical School, Boston, MA 02215, United States
| | - Peng Li
- Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital; and Division of Sleep Medicine, Harvard Medical School, Boston, MA 02215, United States
| | - Steven A. Shea
- Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital; and Division of Sleep Medicine, Harvard Medical School, Boston, MA 02215, United States
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR 97239, United States
| | - Frank A. J. L. Scheer
- Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital; and Division of Sleep Medicine, Harvard Medical School, Boston, MA 02215, United States
| | - Eus J. W. Van Someren
- Netherlands Institute for Neuroscience, Amsterdam, The Netherlands
- Depts. of Integrative Neurophysiology and Psychiatry GGZ inGeest, Center for Neurogenomics and Cognitive Research (CNCR), Neuroscience Campus Amsterdam, VU University and Medical Center, Amsterdam, The Netherlands
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Lo MT, Chiang WY, Hsieh WH, Escobar C, Buijs RM, Hu K. Interactive Effects of Dorsomedial Hypothalamic Nucleus and Time-Restricted Feeding on Fractal Motor Activity Regulation. Front Physiol 2016; 7:174. [PMID: 27242548 PMCID: PMC4870237 DOI: 10.3389/fphys.2016.00174] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 05/02/2016] [Indexed: 01/09/2023] Open
Abstract
One evolutionary adaptation in motor activity control of animals is the anticipation of food that drives foraging under natural conditions and is mimicked in laboratory with daily scheduled food availability. Food anticipation is characterized by increased activity a few hours before the feeding period. Here we report that 2-h food availability during the normal inactive phase of rats not only increases activity levels before the feeding period but also alters the temporal organization of motor activity fluctuations over a wide range of time scales from minutes up to 24 h. We demonstrate this multiscale alteration by assessing fractal patterns in motor activity fluctuations—similar fluctuation structure at different time scales—that are robust in intact animals with ad libitum food access but are disrupted under food restriction. In addition, we show that fractal activity patterns in rats with ad libitum food access are also perturbed by lesion of the dorsomedial hypothalamic (DMH)—a neural node that is involved in food anticipatory behavior. Instead of further disrupting fractal regulation, food restriction restores the disrupted fractal patterns in these animals after the DMH lesion despite the persistence of the 24-h rhythms. This compensatory effect of food restriction is more clearly pronounced in the same animals after the additional lesion of the suprachiasmatic nucleus (SCN)—the central master clock in the circadian system that generates and orchestrates circadian rhythms in behavior and physiological functions in synchrony with day-night cycles. Moreover, all observed influences of food restriction persist even when data during the food anticipatory and feeding period are excluded. These results indicate that food restriction impacts dynamics of motor activity at different time scales across the entire circadian/daily cycle, which is likely caused by the competition between the food-induced time cue and the light-entrained circadian rhythm of the SCN. The differential impacts of food restriction on fractal activity control in intact and DMH-lesioned animals suggest that the DMH plays a crucial role in integrating these different time cues to the circadian network for multiscale regulation of motor activity.
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Affiliation(s)
- Men-Tzung Lo
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Harvard Medical SchoolBoston, MA, USA; Institute of Translational and Interdisciplinary Medicine and Department of Biomedical Sciences and Engineering, National Central UniversityTaoyuan, Taiwan
| | - Wei-Yin Chiang
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Harvard Medical School Boston, MA, USA
| | - Wan-Hsin Hsieh
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Harvard Medical School Boston, MA, USA
| | - Carolina Escobar
- Departamento de Anatomía, Facultad de Medicina, Edificio "B" 4° Piso, Universidad Nacional Autónoma de México México, Mexico
| | - Ruud M Buijs
- Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México México, Mexico
| | - Kun Hu
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Harvard Medical School Boston, MA, USA
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Qian J, Scheer FAJL. Circadian System and Glucose Metabolism: Implications for Physiology and Disease. Trends Endocrinol Metab 2016; 27:282-293. [PMID: 27079518 PMCID: PMC4842150 DOI: 10.1016/j.tem.2016.03.005] [Citation(s) in RCA: 211] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 03/07/2016] [Accepted: 03/07/2016] [Indexed: 12/24/2022]
Abstract
The circadian system serves one of the most fundamental properties present in nearly all organisms: it generates 24-h rhythms in behavioral and physiological processes and enables anticipating and adapting to daily environmental changes. Recent studies indicate that the circadian system is important in regulating the daily rhythm in glucose metabolism. Disturbance of this circadian control or of its coordination relative to the environmental/behavioral cycle, such as in shift work, eating late, or due to genetic changes, results in disturbed glucose control and increased type 2 diabetes risk. Therefore, an in-depth understanding of the mechanisms underlying glucose regulation by the circadian system and its disturbance may help in the development of therapeutic interventions against the deleterious health consequences of circadian disruption.
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Affiliation(s)
- Jingyi Qian
- Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA; Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA.
| | - Frank A J L Scheer
- Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA; Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA.
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Chen MC, Chiang WY, Yugay T, Patxot M, Özçivit İB, Hu K, Lu J. Anterior Insula Regulates Multiscale Temporal Organization of Sleep and Wake Activity. J Biol Rhythms 2016; 31:182-93. [PMID: 26825619 DOI: 10.1177/0748730415627035] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The role of specific cortical regions in sleep-regulating circuits is unclear. The anterior insula (AI) has strong reciprocal connectivity with wake and sleep-promoting hypothalamic and brainstem regions, and we hypothesized that the AI regulates patterns of sleep and wakefulness. To test this hypothesis, we lesioned the AI in rats (n = 8) and compared sleep, wake, and activity regulation in these animals with nonlesioned controls (n = 8) with 24-h sleep recordings and chronic infrared activity monitoring. Compared to controls, animals with AI lesions had decreased wakefulness and increased rapid eye movement (REM) sleep and non-REM (NREM) sleep. AI-lesioned animals had shorter wake bouts, especially during the active dark phase. AI-lesioned animals also had more transitions from NREM to REM sleep, especially during the inactive light phase. Chronic infrared monitoring revealed that AI-lesioned animals also had a disturbed temporal organization of locomotor activity at multiple time scales with more random activity fluctuations from 4 to 12 h despite intact circadian rhythms. These results suggest that the AI regulates sleep and activity and contributes to the regulation of sleep and motor behavior rhythmicity across multiple time scales. Dysfunction of the AI may underlie changes in sleep-wake patterns in neurological diseases.
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Affiliation(s)
- Michael C Chen
- Beth Israel Deaconess Medical Center and Harvard Medical School, Department of Neurology, Division of Sleep Medicine, Boston, MA
| | - Wei-Yin Chiang
- Brigham and Women's Hospital and Harvard Medical School, Departments of Neurology and Medicine, Division of Sleep and Circadian Disorders, Boston, MA
| | - Tatiana Yugay
- Brigham and Women's Hospital and Harvard Medical School, Departments of Neurology and Medicine, Division of Sleep and Circadian Disorders, Boston, MA
| | - Melissa Patxot
- Brigham and Women's Hospital and Harvard Medical School, Departments of Neurology and Medicine, Division of Sleep and Circadian Disorders, Boston, MA
| | - İpek Betül Özçivit
- Beth Israel Deaconess Medical Center and Harvard Medical School, Department of Neurology, Division of Sleep Medicine, Boston, MA
| | - Kun Hu
- Brigham and Women's Hospital and Harvard Medical School, Departments of Neurology and Medicine, Division of Sleep and Circadian Disorders, Boston, MA
| | - Jun Lu
- Beth Israel Deaconess Medical Center and Harvard Medical School, Department of Neurology, Division of Sleep Medicine, Boston, MA
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Ishii M, Iadecola C. Metabolic and Non-Cognitive Manifestations of Alzheimer's Disease: The Hypothalamus as Both Culprit and Target of Pathology. Cell Metab 2015; 22:761-76. [PMID: 26365177 PMCID: PMC4654127 DOI: 10.1016/j.cmet.2015.08.016] [Citation(s) in RCA: 144] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Alzheimer's disease (AD) is increasingly recognized as a complex neurodegenerative disease beginning decades prior to the cognitive decline. While cognitive deficits remain the cardinal manifestation of AD, metabolic and non-cognitive abnormalities, such as alterations in body weight and neuroendocrine functions, are also present, often preceding the cognitive decline. Furthermore, hypothalamic dysfunction can also be a driver of AD pathology. Here we offer a brief appraisal of hypothalamic dysfunction in AD and provide insight into an underappreciated dual role of the hypothalamus as both a culprit and target of AD pathology, as well as into new opportunities for therapeutic interventions and biomarker development.
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Affiliation(s)
- Makoto Ishii
- Feil Family Brain and Mind Research Institute, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA.
| | - Costantino Iadecola
- Feil Family Brain and Mind Research Institute, Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10065, USA
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Zueva MV. Fractality of sensations and the brain health: the theory linking neurodegenerative disorder with distortion of spatial and temporal scale-invariance and fractal complexity of the visible world. Front Aging Neurosci 2015; 7:135. [PMID: 26236232 PMCID: PMC4502359 DOI: 10.3389/fnagi.2015.00135] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 07/02/2015] [Indexed: 11/26/2022] Open
Abstract
The theory that ties normal functioning and pathology of the brain and visual system with the spatial-temporal structure of the visual and other sensory stimuli is described for the first time in the present study. The deficit of fractal complexity of environmental influences can lead to the distortion of fractal complexity in the visual pathways of the brain and abnormalities of development or aging. The use of fractal light stimuli and fractal stimuli of other modalities can help to restore the functions of the brain, particularly in the elderly and in patients with neurodegenerative disorders or amblyopia. Non-linear dynamics of these physiological processes have a strong base of evidence, which is seen in the impaired fractal regulation of rhythmic activity in aged and diseased brains. From birth to old age, we live in a non-linear world, in which objects and processes with the properties of fractality and non-linearity surround us. Against this background, the evolution of man took place and all periods of life unfolded. Works of art created by man may also have fractal properties. The positive influence of music on cognitive functions is well-known. Insufficiency of sensory experience is believed to play a crucial role in the pathogenesis of amblyopia and age-dependent diseases. The brain is very plastic in its early development, and the plasticity decreases throughout life. However, several studies showed the possibility to reactivate the adult's neuroplasticity in a variety of ways. We propose that a non-linear structure of sensory information on many spatial and temporal scales is crucial to the brain health and fractal regulation of physiological rhythms. Theoretical substantiation of the author's theory is presented. Possible applications and the future research that can experimentally confirm or refute the theoretical concept are considered.
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Affiliation(s)
- Marina V. Zueva
- The Division of Clinical Physiology of Vision, Federal State Budgetary Institution “Moscow Helmholtz Research Institute of Eye Diseases" of the Ministry of Healthcare of the Russian FederationMoscow, Russia
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Lack of exercise leads to significant and reversible loss of scale invariance in both aged and young mice. Proc Natl Acad Sci U S A 2015; 112:2320-4. [PMID: 25675516 DOI: 10.1073/pnas.1424706112] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In healthy humans and other animals, behavioral activity exhibits scale invariance over multiple timescales from minutes to 24 h, whereas in aging or diseased conditions, scale invariance is usually reduced significantly. Accordingly, scale invariance can be a potential marker for health. Given compelling indications that exercise is beneficial for mental and physical health, we tested to what extent a lack of exercise affects scale invariance in young and aged animals. We studied six or more mice in each of four age groups (0.5, 1, 1.5, and 2 y) and observed an age-related deterioration of scale invariance in activity fluctuations. We found that limiting the amount of exercise, by removing the running wheels, leads to loss of scale-invariant properties in all age groups. Remarkably, in both young and old animals a lack of exercise reduced the scale invariance in activity fluctuations to the same level. We next showed that scale invariance can be restored by returning the running wheels. Exercise during the active period also improved scale invariance during the resting period, suggesting that activity during the active phase may also be beneficial for the resting phase. Finally, our data showed that exercise had a stronger influence on scale invariance than the effect of age. The data suggest that exercise is beneficial as revealed by scale-invariant parameters and that, even in young animals, a lack of exercise leads to strong deterioration in these parameters.
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Hsieh WH, Escobar C, Yugay T, Lo MT, Pittman-Polletta B, Salgado-Delgado R, Scheer FAJL, Shea SA, Buijs RM, Hu K. Simulated shift work in rats perturbs multiscale regulation of locomotor activity. J R Soc Interface 2014; 11:rsif.2014.0318. [PMID: 24829282 DOI: 10.1098/rsif.2014.0318] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Motor activity possesses a multiscale regulation that is characterized by fractal activity fluctuations with similar structure across a wide range of timescales spanning minutes to hours. Fractal activity patterns are disturbed in animals after ablating the master circadian pacemaker (suprachiasmatic nucleus, SCN) and in humans with SCN dysfunction as occurs with aging and in dementia, suggesting the crucial role of the circadian system in the multiscale activity regulation. We hypothesized that the normal synchronization between behavioural cycles and the SCN-generated circadian rhythms is required for multiscale activity regulation. To test the hypothesis, we studied activity fluctuations of rats in a simulated shift work protocol that was designed to force animals to be active during the habitual resting phase of the circadian/daily cycle. We found that these animals had gradually decreased mean activity level and reduced 24-h activity rhythm amplitude, indicating disturbed circadian and behavioural cycles. Moreover, these animals had disrupted fractal activity patterns as characterized by more random activity fluctuations at multiple timescales from 4 to 12 h. Intriguingly, these activity disturbances exacerbated when the shift work schedule lasted longer and persisted even in the normal days (without forced activity) following the shift work. The disrupted circadian and fractal patterns resemble those of SCN-lesioned animals and of human patients with dementia, suggesting a detrimental impact of shift work on multiscale activity regulation.
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Affiliation(s)
- Wan-Hsin Hsieh
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA Center for Dynamical Biomarkers and Translational Medicine, National Central University, Chungli 32001, Taiwan, Republic of China
| | - Carolina Escobar
- Departamento de Anatomia, Facultad de Medicina, Edificio 'B' 4 Piso, Universidad Nacional Autónoma de México, México 04510, México
| | - Tatiana Yugay
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Men-Tzung Lo
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA Center for Dynamical Biomarkers and Translational Medicine, National Central University, Chungli 32001, Taiwan, Republic of China
| | - Benjamin Pittman-Polletta
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Roberto Salgado-Delgado
- Laboratorio de Biología Celular Fisiología, Facultad de Ciencias, Universidad Autónoma de San Luis Potosí, San Luis Potosí 78290, México
| | - Frank A J L Scheer
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Steven A Shea
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA Center for Research on Occupational and Environmental Toxicology, Oregon Health and Science University, Portland, OR 97239, USA
| | - Ruud M Buijs
- Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México 04510, México
| | - Kun Hu
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA 02115, USA Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, USA Center for Dynamical Biomarkers and Translational Medicine, National Central University, Chungli 32001, Taiwan, Republic of China
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