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Yehia A, Abulseoud OA. Melatonin: a ferroptosis inhibitor with potential therapeutic efficacy for the post-COVID-19 trajectory of accelerated brain aging and neurodegeneration. Mol Neurodegener 2024; 19:36. [PMID: 38641847 PMCID: PMC11031980 DOI: 10.1186/s13024-024-00728-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 04/15/2024] [Indexed: 04/21/2024] Open
Abstract
The unprecedented pandemic of COVID-19 swept millions of lives in a short period, yet its menace continues among its survivors in the form of post-COVID syndrome. An exponentially growing number of COVID-19 survivors suffer from cognitive impairment, with compelling evidence of a trajectory of accelerated aging and neurodegeneration. The novel and enigmatic nature of this yet-to-unfold pathology demands extensive research seeking answers for both the molecular underpinnings and potential therapeutic targets. Ferroptosis, an iron-dependent cell death, is a strongly proposed underlying mechanism in post-COVID-19 aging and neurodegeneration discourse. COVID-19 incites neuroinflammation, iron dysregulation, reactive oxygen species (ROS) accumulation, antioxidant system repression, renin-angiotensin system (RAS) disruption, and clock gene alteration. These events pave the way for ferroptosis, which shows its signature in COVID-19, premature aging, and neurodegenerative disorders. In the search for a treatment, melatonin shines as a promising ferroptosis inhibitor with its repeatedly reported safety and tolerability. According to various studies, melatonin has proven efficacy in attenuating the severity of certain COVID-19 manifestations, validating its reputation as an anti-viral compound. Melatonin has well-documented anti-aging properties and combating neurodegenerative-related pathologies. Melatonin can block the leading events of ferroptosis since it is an efficient anti-inflammatory, iron chelator, antioxidant, angiotensin II antagonist, and clock gene regulator. Therefore, we propose ferroptosis as the culprit behind the post-COVID-19 trajectory of aging and neurodegeneration and melatonin, a well-fitting ferroptosis inhibitor, as a potential treatment.
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Affiliation(s)
- Asmaa Yehia
- Department of Neuroscience, Graduate School of Biomedical Sciences, Mayo Clinic College of Medicine, Phoenix, AZ, 58054, USA
- Department of Medical Physiology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Osama A Abulseoud
- Department of Neuroscience, Graduate School of Biomedical Sciences, Mayo Clinic College of Medicine, Phoenix, AZ, 58054, USA.
- Department of Psychiatry and Psychology, Mayo Clinic Arizona, 5777 E Mayo Blvd, Phoenix, AZ, 85054, USA.
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Davis C, Huggins CE, Kleve S, Leung GKW, Bonham MP. Conceptualizing weight management for night shift workers: A mixed-methods systematic review. Obes Rev 2024; 25:e13659. [PMID: 37985937 DOI: 10.1111/obr.13659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/24/2023] [Accepted: 10/01/2023] [Indexed: 11/22/2023]
Abstract
Shift workers have an increased risk of obesity and metabolic conditions. This mixed-methods systematic literature review on night shift workers aimed to: (1) identify barriers/enablers of weight management; (2) examine effectiveness of weight management interventions; and (3) determine whether interventions addressed enablers/barriers. Six databases were searched, articles screened by title/abstract, followed by full-text review, and quality assessment. Eligible qualitative studies documented experiences of behaviors related to weight change. Eligible quantitative studies were behavior change interventions with weight/body mass index outcomes. A thematic synthesis was undertaken for qualitative studies using the social-ecological model (SEM). Interventions were synthesized narratively including: weight/body composition change; components mapped by behavior change taxonomy; and SEM. A synthesis was undertaken to identify if interventions addressed perceived enablers/barriers. Eight qualitative (n = 169 participants) and 12 quantitative studies (n = 1142 participants) were included. Barriers predominated discussions: intrapersonal (time, fatigue, stress); interpersonal (work routines/cultural norms); organizational (fatigue, lack of: routine, healthy food options, breaks/predictable work); community (lack of healthy food options). The primary outcome for interventions was not weight loss and most did not address many identified enablers/barriers. One intervention reported a clinically significant weight loss result. Weight loss interventions that address barriers/enablers at multiple SEM levels are needed.
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Affiliation(s)
- Corinne Davis
- Department of Nutrition, Dietetics and Food, Faculty of Medicine, Nursing and Health Sciences, Monash University, Notting Hill, Australia
| | - Catherine E Huggins
- Department of Nutrition, Dietetics and Food, Faculty of Medicine, Nursing and Health Sciences, Monash University, Notting Hill, Australia
- Institute for Health Transformation, Global Centre for Preventive Health and Nutrition, School of Health and Social Development, Faculty of Health, Deakin University, Geelong, Australia
| | - Sue Kleve
- Department of Nutrition, Dietetics and Food, Faculty of Medicine, Nursing and Health Sciences, Monash University, Notting Hill, Australia
| | - Gloria K W Leung
- Department of Nutrition, Dietetics and Food, Faculty of Medicine, Nursing and Health Sciences, Monash University, Notting Hill, Australia
| | - Maxine P Bonham
- Department of Nutrition, Dietetics and Food, Faculty of Medicine, Nursing and Health Sciences, Monash University, Notting Hill, Australia
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Broussard JL, Knud-Hansen BC, Grady S, Knauer OA, Ronda JM, Aeschbach D, Czeisler CA, Wright KP. Influence of circadian phase and extended wakefulness on glucose levels during forced desynchrony. Sleep Health 2024; 10:S96-S102. [PMID: 37996284 PMCID: PMC11031343 DOI: 10.1016/j.sleh.2023.10.010] [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: 03/31/2023] [Revised: 09/23/2023] [Accepted: 10/18/2023] [Indexed: 11/25/2023]
Abstract
OBJECTIVES Circadian misalignment and sleep deprivation often occur in tandem, and both negatively impact glucose homeostasis and metabolic health. The present study employed a forced desynchrony protocol to examine the influence of extended wakefulness and circadian misalignment on hourly glucose levels. METHODS Nine healthy adults (4F/5M; 26 ± 4years) completed a 31-day in-laboratory protocol. After three 24 hour baseline days with 8 hours scheduled sleep opportunities, participants were scheduled to 14 consecutive 42.85 hour sleep-wake cycles, with 28.57 hours extended wakefulness and 14.28 hours sleep opportunities each cycle. Blood was sampled hourly across the forced desynchrony and over 600 plasma samples per participant were analyzed for glucose levels. RESULTS Both hours into the 42.85 hours forced desynchrony day and circadian phase modulated glucose levels (p < .0001). Glucose peaked after each meal during scheduled wakefulness and decreased during scheduled sleep/fasting. Glucose levels were, on average, lowest during the biological daytime and rose throughout the biological night, peaking in the biological morning. When analyzed separately for scheduled sleep vs. wakefulness, the peak timing of the circadian rhythm in glucose was later during sleep (p < .05). Glucose area under the curve levels increased rapidly from the beginning of the forced desynchrony protocol and were highest on the second forced desynchrony day (p < .01), returning towards forced desynchrony day 1 levels thereafter. CONCLUSIONS These findings have important implications for understanding factors contributing to altered glucose metabolism during sleep loss and circadian misalignment, and for potential physiological adaptation of metabolism in healthy adults, who are increasingly exposed to such conditions in our society.
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Affiliation(s)
- Josiane L Broussard
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder, Colorado, USA; Sleep and Metabolism Laboratory, Department of Health and Exercise Science, Colorado State University, Fort Collins, Colorado, USA.
| | - Brent C Knud-Hansen
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder, Colorado, USA; Sleep and Metabolism Laboratory, Department of Health and Exercise Science, Colorado State University, Fort Collins, Colorado, USA
| | - Scott Grady
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, Massachusetts, USA; Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts, USA; Portland Diabetes and Endocrinology Center, PC, Portland, Oregon, USA
| | - Oliver A Knauer
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder, Colorado, USA
| | - Joseph M Ronda
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, Massachusetts, USA; Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Daniel Aeschbach
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, Massachusetts, USA; Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts, USA; Department of Sleep and Human Factors Research, Institute of Aerospace Medicine, German Aerospace Center, Cologne, Germany
| | - Charles A Czeisler
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, Massachusetts, USA; Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts, USA.
| | - Kenneth P Wright
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder, Colorado, USA; Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, Massachusetts, USA; Division of Sleep Medicine, Harvard Medical School, Boston, Massachusetts, USA.
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4
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Teixeira BS, Silva CM, Silva ATF, Santos LLD, de Paiva Maia YC, Pedrazzoli M, Wright KP, Crispim CA. Influence of fasting during the night shift on next day eating behavior, hunger, and glucose and insulin levels: a randomized, three-condition, crossover trial. Eur J Nutr 2023; 62:1281-1293. [PMID: 36526739 DOI: 10.1007/s00394-022-03069-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 12/01/2022] [Indexed: 12/23/2022]
Abstract
AIMS To investigate the influence of fasting during the night shift on eating behavior, hunger, glucose and insulin levels the following day. METHODS Study with 10 male police officers who have been working at night. Participants were tested under three different conditions separated by at least 6 days of washout in a randomized, crossover design: "Night Shift Fasting" (NSF)-two nights of fasting during the night shift; "Night Shift Eating" (NSE)-two nights with the consumption of a standardized meal during the night shift (678 ± 42 kcal consumed at ~ 0200 h); and "Nighttime Sleep" (NS)-two nights of sleep. The morning after, blood glucose and insulin and hunger ratings were assessed, and food intake was assessed with an ad libitum test meal. Food intake was also assessed throughout the remainder of the day using a food record. Generalized Estimating Equations were used to analyze the effect of experimental condition. RESULTS Food intake during the test meal, especially of proteins and fats, was higher after fasting during the night shift compared to the other conditions (p < 0.05), whereas desire to eat scores were lower after the NSF compared to NSE condition (p = 0.043). Hunger levels were lower after the NSF compared to the NS condition (p = 0.012). Insulin and HOMA-IR were also lower in the morning after NSF (p < 0.001). CONCLUSION Fasting during the night shift leads to not only a higher intake of energy and macronutrients both in the early morning after work and throughout the next day, but also lower insulin levels and HOMA-IR in the morning. REGISTRATION NUMBER OF CLINICAL TRIAL NCT03800732. Initial release: 01/09/2019. Last release: 02/23/2022.
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Affiliation(s)
- Bruno Simão Teixeira
- Chrononutrition Research Group, School of Medicine, Faculty of Medicine, Federal University of Uberlândia, Av. Para, 1720, Bloco 2U, Sala 20. Campus Umuarama, Uberlândia, Minas Gerais, 38405-320, Brazil
| | - Catarina Mendes Silva
- Chrononutrition Research Group, School of Medicine, Faculty of Medicine, Federal University of Uberlândia, Av. Para, 1720, Bloco 2U, Sala 20. Campus Umuarama, Uberlândia, Minas Gerais, 38405-320, Brazil
| | - Alinne Tatiane Faria Silva
- Molecular Biology and Nutrition Research Group, School of Medicine, Federal University of Uberlândia, Uberlândia, Minas Gerais, 38405-320, Brazil
| | - Letícia Lopes Dantas Santos
- Molecular Biology and Nutrition Research Group, School of Medicine, Federal University of Uberlândia, Uberlândia, Minas Gerais, 38405-320, Brazil
| | - Yara Cristina de Paiva Maia
- Molecular Biology and Nutrition Research Group, School of Medicine, Federal University of Uberlândia, Uberlândia, Minas Gerais, 38405-320, Brazil
| | - Mario Pedrazzoli
- School of Arts, Sciences and Humanities of University of São Paulo, São Paulo, Brazil
| | - Kenneth P Wright
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, 80309-0354, USA
| | - Cibele Aparecida Crispim
- Chrononutrition Research Group, School of Medicine, Faculty of Medicine, Federal University of Uberlândia, Av. Para, 1720, Bloco 2U, Sala 20. Campus Umuarama, Uberlândia, Minas Gerais, 38405-320, Brazil.
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Wang W, Yuan RK, Mitchell JF, Zitting KM, St Hilaire MA, Wyatt JK, Scheer FAJL, Wright KP, Brown EN, Ronda JM, Klerman EB, Duffy JF, Dijk DJ, Czeisler CA. Desynchronizing the sleep---wake cycle from circadian timing to assess their separate contributions to physiology and behaviour and to estimate intrinsic circadian period. Nat Protoc 2023; 18:579-603. [PMID: 36376588 DOI: 10.1038/s41596-022-00746-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 06/24/2022] [Indexed: 11/16/2022]
Abstract
Circadian clocks drive cyclic variations in many aspects of physiology, but some daily variations are evoked by periodic changes in the environment or sleep-wake state and associated behaviors, such as changes in posture, light levels, fasting or eating, rest or activity and social interactions; thus, it is often important to quantify the relative contributions of these factors. Yet, circadian rhythms and these evoked effects cannot be separated under typical 24-h day conditions, because circadian phase and the length of time awake or asleep co-vary. Nathaniel Kleitman's forced desynchrony (FD) protocol was designed to assess endogenous circadian rhythmicity and to separate circadian from evoked components of daily rhythms in multiple parameters. Under FD protocol conditions, light intensity is kept low to minimize its impact on the circadian pacemaker, and participants have sleep-wake state and associated behaviors scheduled to an imposed non-24-h cycle. The period of this imposed cycle, Τ, is chosen so that the circadian pacemaker cannot entrain to it and therefore continues to oscillate at its intrinsic period (τ, ~24.15 h), ensuring circadian components are separated from evoked components of daily rhythms. Here we provide detailed instructions and troubleshooting techniques on how to design, implement and analyze the data from an FD protocol. We provide two procedures: one with general guidance for designing an FD study and another with more precise instructions for replicating one of our previous FD studies. We discuss estimating circadian parameters and quantifying the separate contributions of circadian rhythmicity and the sleep-wake cycle, including statistical analysis procedures and an R package for conducting the non-orthogonal spectral analysis method that enables an accurate estimation of period, amplitude and phase.
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Affiliation(s)
- Wei Wang
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA.
- Division of Sleep Medicine and Department of Medicine, Harvard Medical School, Boston, MA, USA.
| | - Robin K Yuan
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine and Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Jude F Mitchell
- Department of Brain and Cognitive Sciences, University of Rochester, Rochester, NY, USA
| | - Kirsi-Marja Zitting
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine and Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Melissa A St Hilaire
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine and Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - James K Wyatt
- Department of Psychiatry and Behavioral Sciences, 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 and Department of Medicine, Harvard Medical School, Boston, MA, USA
- Broad Institute, Cambridge, MA, USA
| | - Kenneth P Wright
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Emery N Brown
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA
- Department of Brain and Cognitive Science, Massachusetts Institute of Technology, Cambridge, MA, USA
- Institute for Medical Engineering and Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
- Institute for Data Systems and Society, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Joseph M Ronda
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine and Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Elizabeth B Klerman
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine and Department of Medicine, Harvard Medical School, Boston, MA, USA
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Jeanne F Duffy
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine and Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Derk-Jan Dijk
- Surrey Sleep Research Centre, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
- UK Dementia Research Institute Care Research and Technology Centre, Imperial College London and the University of Surrey, Guildford, UK
| | - Charles A Czeisler
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine and Department of Medicine, Harvard Medical School, Boston, MA, USA
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6
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Chaput JP, McHill AW, Cox RC, Broussard JL, Dutil C, da Costa BGG, Sampasa-Kanyinga H, Wright KP. The role of insufficient sleep and circadian misalignment in obesity. Nat Rev Endocrinol 2023; 19:82-97. [PMID: 36280789 PMCID: PMC9590398 DOI: 10.1038/s41574-022-00747-7] [Citation(s) in RCA: 84] [Impact Index Per Article: 84.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/30/2022] [Indexed: 01/21/2023]
Abstract
Traditional risk factors for obesity and the metabolic syndrome, such as excess energy intake and lack of physical activity, cannot fully explain the high prevalence of these conditions. Insufficient sleep and circadian misalignment predispose individuals to poor metabolic health and promote weight gain and have received increased research attention in the past 10 years. Insufficient sleep is defined as sleeping less than recommended for health benefits, whereas circadian misalignment is defined as wakefulness and food intake occurring when the internal circadian system is promoting sleep. This Review discusses the impact of insufficient sleep and circadian misalignment in humans on appetite hormones (focusing on ghrelin, leptin and peptide-YY), energy expenditure, food intake and choice, and risk of obesity. Some potential strategies to reduce the adverse effects of sleep disruption on metabolic health are provided and future research priorities are highlighted. Millions of individuals worldwide do not obtain sufficient sleep for healthy metabolic functions. Furthermore, modern working patterns, lifestyles and technologies are often not conducive to adequate sleep at times when the internal physiological clock is promoting it (for example, late-night screen time, shift work and nocturnal social activities). Efforts are needed to highlight the importance of optimal sleep and circadian health in the maintenance of metabolic health and body weight regulation.
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Affiliation(s)
- Jean-Philippe Chaput
- Healthy Active Living and Obesity Research Group, CHEO Research Institute, Ottawa, ON, Canada.
- Department of Paediatrics, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada.
| | - Andrew W McHill
- Sleep, Chronobiology, and Health Laboratory, School of Nursing, Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA
| | - Rebecca C Cox
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Josiane L Broussard
- Sleep and Metabolism Laboratory, Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, USA
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Caroline Dutil
- Healthy Active Living and Obesity Research Group, CHEO Research Institute, Ottawa, ON, Canada
- School of Human Kinetics, Faculty of Health Sciences, University of Ottawa, Ottawa, ON, Canada
| | - Bruno G G da Costa
- Research Center in Physical Activity and Health, Department of Physical Education, School of Sports, Federal University of Santa Catarina, Florianopolis, Brazil
| | - Hugues Sampasa-Kanyinga
- Healthy Active Living and Obesity Research Group, CHEO Research Institute, Ottawa, ON, Canada
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, ON, Canada
| | - Kenneth P Wright
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
- Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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7
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Young ME, Latimer MN. Circadian rhythms in cardiac metabolic flexibility. Chronobiol Int 2023; 40:13-26. [PMID: 34162286 PMCID: PMC8695643 DOI: 10.1080/07420528.2021.1939366] [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: 03/30/2021] [Accepted: 06/01/2021] [Indexed: 12/25/2022]
Abstract
Numerous aspects of cardiovascular physiology (e.g., heart rate, blood pressure) and pathology (e.g., myocardial infarction and sudden cardiac death) exhibit time-of-day-dependency. In association with day-night differences in energetic demand and substrate availability, the healthy heart displays remarkable metabolic flexibility through temporal partitioning of the metabolic fate of common substrates (glucose, lipid, amino acids). The purpose of this review is to highlight the contribution that circadian clocks provide toward 24-hr fluctuations in cardiac metabolism and to discuss whether attenuation and/or augmentation of these metabolic rhythms through adjustment of nutrient intake timing impacts cardiovascular disease development.
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Affiliation(s)
- Martin E Young
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama, Birmingham, Alabama, USA
| | - Mary N Latimer
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama, Birmingham, Alabama, USA
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8
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Lu X, Fan Z, Liu A, Liu R, Lou X, Hu J. Extended Inter-Meal Interval Negatively Impacted the Glycemic and Insulinemic Responses after Both Lunch and Dinner in Healthy Subjects. Nutrients 2022; 14:nu14173617. [PMID: 36079874 PMCID: PMC9460893 DOI: 10.3390/nu14173617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/26/2022] [Accepted: 08/29/2022] [Indexed: 11/16/2022] Open
Abstract
This study aimed to investigate the glycemic and insulinemic effects of lunch timing based on a fixed feeding window, and the effects of apple preload on postprandial glucose and insulin responses after nutrient-balanced lunch and the subsequent high-fat dinner in healthy participants. Twenty-six participants completed four randomized, crossover experimental trials: (1) early standardized lunch at 12:00 (12S); (2) apple preload to 12S (12A+S); (3) late standardized lunch at 14:00 (14S); and (4) apple preload to 14S (14A+S); wherein twenty participants’ blood samples were collected for insulin analysis following the lunch trails. In each experimental trial, each participant equipped with a continuous glucose monitor (CGM) was provided with a standardized breakfast and a high-fat dinner to be consumed at 8:00 and 18:00, respectively. The late lunch (14S) resulted in significantly elevated glucose peak, delayed insulin peak time, decreased insulin sensitivity, and increased insulin resistance following the lunch; also decreased glycemic response following the subsequent dinner and larger blood glucose fluctuation over the 24-h period compared with the 12S. The 14A+S significantly reduced the glucose peak, the insulin peak time and the glycemic variability following the lunch, also the 24-h glycemic variability compared with the 14S. The insulin sensitivity was significantly improved in the 12A+S, compared with that of the 12S. In conclusion, the present study found that an extra 2-h inter-meal fasting before and after lunch resulted in elevated glycemic response in both macronutrient-balanced meal and high-fat meal in healthy subjects. The negative impact of a late lunch could be partly reversed by the apple preload, without a trade-off of insulin secretion.
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Affiliation(s)
- Xuejiao Lu
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Zhihong Fan
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing 100083, China
- Correspondence: ; Tel.: +86-10-62737717
| | - Anshu Liu
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Rui Liu
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Xinling Lou
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Jiahui Hu
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
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9
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Lentjes MAH, Oude Griep LM, Mulligan AA, Montgomery S, Wareham NJ, Khaw KT. Face Validity of Observed Meal Patterns Reported with 7-Day Diet Diaries in a Large Population-Based Cohort Using Diurnal Variation in Concentration Biomarkers of Dietary Intake. Nutrients 2022; 14:238. [PMID: 35057419 PMCID: PMC8780432 DOI: 10.3390/nu14020238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 12/26/2021] [Accepted: 12/28/2021] [Indexed: 12/04/2022] Open
Abstract
In a cross-sectional analysis of a population-based cohort (United Kingdom, N = 21,318, 1993-1998), we studied how associations between meal patterns and non-fasting triglyceride and glucose concentrations were influenced by the hour of day at which the blood sample was collected to ascertain face validity of reported meal patterns, as well as the influence of reporting bias (assessed using formula of energy expenditure) on this association. Meal size (i.e., reported energy content), mealtime and meal frequency were reported using pre-structured 7-day diet diaries. In ANCOVA, sex-specific means of biomarker concentrations were calculated by hour of blood sample collection for quartiles of reported energy intake at breakfast, lunch and dinner (meal size). Significant interactions were observed between breakfast size, sampling time and triglyceride concentrations and between lunch size, sampling time and triglyceride, as well as glucose concentrations. Those skipping breakfast had the lowest triglyceride concentrations in the morning and those skipping lunch had the lowest triglyceride and glucose concentrations in the afternoon, especially among acceptable energy reporters. Eating and drinking occasion frequency was weakly associated with glucose concentrations in women and positively associated with triglyceride concentrations in both sexes; stronger associations were observed for larger vs. smaller meals and among acceptable energy reporters. Associations between meal patterns and concentration biomarkers can be observed when accounting for diurnal variation and underreporting. These findings support the use of 7-day diet diaries for studying associations between meal patterns and health.
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Affiliation(s)
- Marleen A. H. Lentjes
- Department of Public Health and Primary Care, University of Cambridge, Cambridge CB1 8RN, UK; (A.A.M.); (K.-T.K.)
- Clinical Epidemiology and Biostatistics/Nutrition Gut Brain Interactions Research Centre, School of Medical Sciences, Örebro University, 70182 Örebro, Sweden;
| | - Linda M. Oude Griep
- MRC Epidemiology Unit, Institute of Metabolic Sciences, University of Cambridge, Cambridge CB2 0QQ, UK; (L.M.O.G.); (N.J.W.)
- NIHR Biomedical Research Centre, Diet, Anthropometry and Physical Activity (DAPA) Group, MRC Epidemiology Unit, University of Cambridge, Cambridge CB2 0QQ, UK
| | - Angela A. Mulligan
- Department of Public Health and Primary Care, University of Cambridge, Cambridge CB1 8RN, UK; (A.A.M.); (K.-T.K.)
- NIHR Biomedical Research Centre, Diet, Anthropometry and Physical Activity (DAPA) Group, MRC Epidemiology Unit, University of Cambridge, Cambridge CB2 0QQ, UK
| | - Scott Montgomery
- Clinical Epidemiology and Biostatistics/Nutrition Gut Brain Interactions Research Centre, School of Medical Sciences, Örebro University, 70182 Örebro, Sweden;
- Clinical Epidemiology Division, Department of Medicine, Solna, Karolinska Institute, 17177 Stockholm, Sweden
- Department of Epidemiology and Public Health, University College London, London WC1E 6BT, UK
| | - Nick J. Wareham
- MRC Epidemiology Unit, Institute of Metabolic Sciences, University of Cambridge, Cambridge CB2 0QQ, UK; (L.M.O.G.); (N.J.W.)
| | - Kay-Tee Khaw
- Department of Public Health and Primary Care, University of Cambridge, Cambridge CB1 8RN, UK; (A.A.M.); (K.-T.K.)
- School of Clinical Medicine/Clinical Gerontology, University of Cambridge, Cambridge CB1 8RN, UK
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10
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Grant LK, St Hilaire MA, Brainard GC, Czeisler CA, Lockley SW, Rahman SA. Endogenous circadian regulation and phase resetting of clinical metabolic biomarkers. J Pineal Res 2021; 71:e12752. [PMID: 34118084 DOI: 10.1111/jpi.12752] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 06/09/2021] [Accepted: 06/10/2021] [Indexed: 11/30/2022]
Abstract
Shiftwork and circadian disruption are associated with adverse metabolic effects. Therefore, we examined whether clinical biomarkers of metabolic health are under endogenous circadian regulation using a 40 hours constant routine protocol (CR; constant environmental and behavioral conditions) and evaluated the impact of typical daily conditions with periodic sleep and meals (baseline; 8 hours sleep at night, four meals during a 16 hour wake episode) on the phase and amplitude of these rhythms. Additionally, we tested whether these circadian rhythms are reset during simulated shiftwork. Under CR (n = 16 males, mean age ± SD = 23.4 ± 2.3 years), we found endogenous circadian rhythms in cholesterol, HDL and LDL, albumin and total protein, and VLDL and triglyceride. The rhythms were masked under baseline conditions except for cholesterol, which had near-identical phases under both conditions. Resetting of the cholesterol rhythm and Dim Light Melatonin Onset (DLMO) was then tested in a study of simulated shiftwork (n = 25, 14 females, 36.3 ± 8.9 years) across four protocols; two with abrupt 8 hour delay shifts and exposure to either blue-enriched or standard white light; and either an abrupt or gradual 8 hour advance (1.6 hours/day over 5 days) both with exposure to blue-enriched white light. In the delay protocols, the cholesterol rhythm shifted later by -3.7 hours and -4.2 hours, respectively, compared to -6.6 hours and -4.7 hours, for DLMO. There was a significant advance in cholesterol in the abrupt (+5.1 hours) but not the gradual (+2.1 hours) protocol, compared to +3.1 hours and +2.8 hours in DLMO, respectively. Exploratory group analysis comparing the phases of all metabolic biomarkers under both studies showed evidence of phase shifts due to simulated shiftwork. These results show that clinical biomarkers of metabolic health are under endogenous circadian regulation but that the expression of these rhythms is substantially influenced by environmental factors. These rhythms can also be reset, which has implications for understanding how both behavioral changes and circadian shifts due to shiftwork may disrupt metabolic function.
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Affiliation(s)
- Leilah K Grant
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
| | - Melissa A St Hilaire
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
| | - George C Brainard
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Charles A Czeisler
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
| | - Steven W Lockley
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
| | - Shadab A Rahman
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, MA, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
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11
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Street ME, Sartori C, Catellani C, Righi B. Precocious Puberty and Covid-19 Into Perspective: Potential Increased Frequency, Possible Causes, and a Potential Emergency to Be Addressed. Front Pediatr 2021; 9:734899. [PMID: 34616700 PMCID: PMC8488256 DOI: 10.3389/fped.2021.734899] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 08/20/2021] [Indexed: 01/01/2023] Open
Abstract
A significant increase in precocious puberty, rapidly progressive puberty and precocious menarche has been reported in Italy since the initial lockdown because of the pandemic, and this could represent a new emergency to be addressed during this pandemic. There is a need, therefore, for further understanding and research. Many causes could account for this. Initially, it was thought that the changes in life-style, in screen time, and sleeping habits could be the cause but if considered individually these are insufficient to explain this phenomenon. Likely, changes in central nervous mediators, and an increase in catecholamines could contribute as a trigger, however, these aspects are poorly studied and understood as well as the real perceptions of these children. Finally, staying more indoors has certainly exposed these children to specific contaminants working as endocrine disruptors which could also have had an effect. It would be of utmost importance to compare this phenomenon worldwide with appropriate studies in order to verify what is happening, and gain a new insight into the consequences of the covid-19 pandemic and into precocious puberty and for future prevention.
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Affiliation(s)
- Maria E Street
- Division of Pediatric Endocrinology and Diabetology, Unit of Pediatrics, Department of Mother and Child, Azienda USL-IRCCS di Reggio Emilia, Reggio Emilia, Italy
| | - Chiara Sartori
- Division of Pediatric Endocrinology and Diabetology, Unit of Pediatrics, Department of Mother and Child, Azienda USL-IRCCS di Reggio Emilia, Reggio Emilia, Italy
| | - Cecilia Catellani
- Division of Pediatric Endocrinology and Diabetology, Unit of Pediatrics, Department of Mother and Child, Azienda USL-IRCCS di Reggio Emilia, Reggio Emilia, Italy.,PhD Program in Clinical and Experimental Medicine, University of Modena and Reggio Emilia, Modena, Italy
| | - Beatrice Righi
- Division of Pediatric Endocrinology and Diabetology, Unit of Pediatrics, Department of Mother and Child, Azienda USL-IRCCS di Reggio Emilia, Reggio Emilia, Italy
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12
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Loizides-Mangold U, Petrenko V, Dibner C. Circadian Lipidomics: Analysis of Lipid Metabolites Around the Clock. Methods Mol Biol 2020; 2130:169-183. [PMID: 33284444 DOI: 10.1007/978-1-0716-0381-9_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
Lipidomics has been defined as the large-scale analysis of lipids in organelles, cells, tissues, or whole organisms. Including the temporal aspects of lipid metabolic changes into this analysis allows to access yet another important aspect of lipid regulation. The resulting methodology, circadian lipidomics, has thus emerged as a novel tool to address the enormous complexity, which is present among cellular lipids. Here, we describe how mass spectrometry-based circadian lipidomics can be applied to study the impact of peripheral clocks on lipid metabolism in human primary cells and tissues, exemplified by studies in human pancreatic islets and skeletal myotubes.
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Affiliation(s)
- Ursula Loizides-Mangold
- Division of Endocrinology, Diabetes and Nutrition Division, Department of Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Institute of Genetics and Genomics in Geneva (iGE3), Geneva, Switzerland
- Diabetes Center of the Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Volodymyr Petrenko
- Division of Endocrinology, Diabetes and Nutrition Division, Department of Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Institute of Genetics and Genomics in Geneva (iGE3), Geneva, Switzerland
- Diabetes Center of the Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Charna Dibner
- Division of Endocrinology, Diabetes and Nutrition Division, Department of Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
- Institute of Genetics and Genomics in Geneva (iGE3), Geneva, Switzerland.
- Diabetes Center of the Faculty of Medicine, University of Geneva, Geneva, Switzerland.
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13
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The importance of 24-h metabolism in obesity-related metabolic disorders: opportunities for timed interventions. Int J Obes (Lond) 2020; 45:479-490. [PMID: 33235354 DOI: 10.1038/s41366-020-00719-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 09/18/2020] [Accepted: 11/03/2020] [Indexed: 11/08/2022]
Abstract
Various metabolic processes in the body oscillate throughout the natural day, driven by a biological clock. Circadian rhythms are also influenced by time cues from the environment (light exposure) and behaviour (eating and exercise). Recent evidence from diurnal- and circadian-rhythm studies indicates rhythmicity in various circulating metabolites, insulin secretion and -sensitivity and energy expenditure in metabolically healthy adults. These rhythms have been shown to be disturbed in adults with obesity-related metabolic disturbances. Moreover, eating and being (in)active at a time that the body is not prepared for it, as in night-shift work, is related to poor metabolic outcomes. These findings indicate the relevance of 24-h metabolism in obesity-related metabolic alterations and have also led to novel strategies, such as timing of food intake and exercise, to reinforce the circadian rhythm and thereby improving metabolic health. This review aims to deepen the understanding of the influence of the circadian system on metabolic processes and obesity-related metabolic disturbances and to discuss novel time-based strategies that may be helpful in combating metabolic disease.
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14
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Chung N, Bin YS, Cistulli PA, Chow CM. Does the Proximity of Meals to Bedtime Influence the Sleep of Young Adults? A Cross-Sectional Survey of University Students. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17082677. [PMID: 32295235 PMCID: PMC7215804 DOI: 10.3390/ijerph17082677] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 04/01/2020] [Accepted: 04/10/2020] [Indexed: 01/09/2023]
Abstract
Avoiding food before bedtime is a widely accepted sleep hygiene practice, yet few studies have assessed meal timing as a risk factor for disrupted sleep. This study examined the relationship between evening meal timing and sleep quality in young adults. A total of N = 793 participants (26% male) aged between 18 and 29 years responded to an online survey, which captured sociodemographic information, lifestyle variables, and sleep characteristics. Meal timing was defined as meals more than 3 h before or within 3 h of bedtime. The outcomes were as follows: one or more nocturnal awakenings, sleep onset latency of >30 min, and sleep duration of ≤6 h. Logistic regression analyses showed that eating within 3 h of bedtime was positively associated with nocturnal awakening (OR = 1.61, 95% CI = 1.15–2.27) but not long sleep onset latency (1.24; 0.89–1.73) or short sleep duration (0.79; 0.49–1.26). The relationship remained significant after adjusting for potential confounders of ethnicity and body mass index (OR = 1.43, 95% CI = 1.00–2.04). Meal timing appears to be a modifiable risk factor for nocturnal awakenings and disrupted sleep. However, this is a preliminary cross-sectional study and highlights the need for additional research on the influence of the timing of food intake on sleep.
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Affiliation(s)
- Nikola Chung
- Sydney Medical School, University of Sydney, Sydney 2006, Australia; (N.C.); (P.A.C.)
| | - Yu Sun Bin
- Sydney Medical School, University of Sydney, Sydney 2006, Australia; (N.C.); (P.A.C.)
- Sleep Research Group, Charles Perkins Centre, University of Sydney, Sydney 2006, Australia;
- Correspondence: ; Tel.: +61-2-8627-6113
| | - Peter A. Cistulli
- Sydney Medical School, University of Sydney, Sydney 2006, Australia; (N.C.); (P.A.C.)
- Sleep Research Group, Charles Perkins Centre, University of Sydney, Sydney 2006, Australia;
| | - Chin Moi Chow
- Sleep Research Group, Charles Perkins Centre, University of Sydney, Sydney 2006, Australia;
- Sydney School of Health Sciences, University of Sydney, Sydney 2006, Australia
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15
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Mason IC, Qian J, Adler GK, Scheer FAJL. Impact of circadian disruption on glucose metabolism: implications for type 2 diabetes. Diabetologia 2020; 63:462-472. [PMID: 31915891 PMCID: PMC7002226 DOI: 10.1007/s00125-019-05059-6] [Citation(s) in RCA: 135] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 08/19/2019] [Indexed: 12/21/2022]
Abstract
The circadian system generates endogenous rhythms of approximately 24 h, the synchronisation of which are vital for healthy bodily function. The timing of many physiological processes, including glucose metabolism, are coordinated by the circadian system, and circadian disruptions that desynchronise or misalign these rhythms can result in adverse health outcomes. In this review, we cover the role of the circadian system and its disruption in glucose metabolism in healthy individuals and individuals with type 2 diabetes mellitus. We begin by defining circadian rhythms and circadian disruption and then we provide an overview of circadian regulation of glucose metabolism. We next discuss the impact of circadian disruptions on glucose control and type 2 diabetes. Given the concurrent high prevalence of type 2 diabetes and circadian disruption, understanding the mechanisms underlying the impact of circadian disruption on glucose metabolism may aid in improving glycaemic control.
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Affiliation(s)
- Ivy C Mason
- Brigham and Women's Hospital, Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, 221 Longwood Avenue, Boston, MA, 02115, USA
- Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Jingyi Qian
- Brigham and Women's Hospital, Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, 221 Longwood Avenue, Boston, MA, 02115, USA
- Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Gail K Adler
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Frank A J L Scheer
- Brigham and Women's Hospital, Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, 221 Longwood Avenue, Boston, MA, 02115, USA.
- Division of Sleep Medicine, Department of Medicine, Harvard Medical School, Boston, MA, USA.
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16
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Regan MD, Flynn-Evans EE, Griko YV, Kilduff TS, Rittenberger JC, Ruskin KJ, Buck CL. Shallow metabolic depression and human spaceflight: a feasible first step. J Appl Physiol (1985) 2020; 128:637-647. [PMID: 31999524 DOI: 10.1152/japplphysiol.00725.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Synthetic torpor is an induced state of deep metabolic depression (MD) in an organism that does not naturally employ regulated and reversible MD. If applied to spaceflight crewmembers, this metabolic state may theoretically mitigate numerous biological and logistical challenges of human spaceflight. These benefits have been the focus of numerous recent articles where, invariably, they are discussed in the context of hypothetical deep MD states in which the metabolism of crewmembers is profoundly depressed relative to basal rates. However, inducing these deep MD states in humans, particularly humans aboard spacecraft, is currently impossible. Here, we discuss shallow MD as a feasible first step toward synthetic torpor during spaceflight and summarize perspectives following a recent NASA-hosted workshop. We discuss methods to safely induce shallow MD (e.g., sleep and slow wave enhancement via acoustic and photoperiod stimulation; moderate sedation via dexmedetomidine), which we define as an ~20% depression of metabolic rate relative to basal levels. We also discuss different modes of shallow MD application (e.g., habitual versus targeted, whereby shallow MD is induced routinely throughout a mission or only under certain circumstances, respectively) and different spaceflight scenarios that would benefit from its use. Finally, we propose a multistep development plan toward the application of synthetic torpor to human spaceflight, highlighting shallow MD's role. As space agencies develop missions to send humans further into space than ever before, shallow MD has the potential to confer health benefits for crewmembers, reduce demands on spacecraft capacities, and serve as a testbed for deeper MD technologies.
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Affiliation(s)
- Matthew D Regan
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, Wisconsin
| | - Erin E Flynn-Evans
- Fatigue Countermeasures Laboratory, Human Systems Integration Division, NASA Ames Research Center, Moffett Field, California
| | - Yuri V Griko
- Countermeasure Development Laboratory, Space Biosciences Division, NASA Ames Research Center, Moffett Field, California
| | - Thomas S Kilduff
- Biosciences Division, Center for Neuroscience, SRI International, Menlo Park, California
| | - Jon C Rittenberger
- Guthrie Robert Packer Hospital Emergency Medicine Program, Geisinger Commonwealth School of Medicine, Scranton, Pennsylvania
| | - Keith J Ruskin
- Department of Anesthesia and Critical Care, University of Chicago, Chicago, Illinois
| | - C Loren Buck
- Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona
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17
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Liu L, Xie B, Fan M, Candas-Green D, Jiang JX, Wei R, Wang Y, Chen HW, Hu Y, Li JJ. Low-Level Saturated Fatty Acid Palmitate Benefits Liver Cells by Boosting Mitochondrial Metabolism via CDK1-SIRT3-CPT2 Cascade. Dev Cell 2019; 52:196-209.e9. [PMID: 31866205 DOI: 10.1016/j.devcel.2019.11.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 10/10/2019] [Accepted: 11/18/2019] [Indexed: 12/20/2022]
Abstract
Saturated fatty acids (SFAs) (the "bad" fat), especially palmitate (PA), in the human diet are blamed for potential health risks such as obesity and cancer because of SFA-induced lipotoxicity. However, epidemiological results demonstrate a latent benefit of SFAs, and it remains elusive whether a certain low level of SFAs is physiologically essential for maintaining cell metabolic hemostasis. Here, we demonstrate that although high-level PA (HPA) indeed induces lipotoxic effects in liver cells, low-level PA (LPA) increases mitochondrial functions and alleviates the injuries induced by HPA or hepatoxic agent carbon tetrachloride (CCl4). LPA treatment in mice enhanced liver mitochondrial activity and reduced CCl4 hepatotoxicity with improved blood levels of aspartate aminotransferase (AST), alanine transaminase (ALT), and mitochondrial aspartate transaminase (m-AST). LPA-mediated mitochondrial homeostasis is regulated by CDK1-mediated SIRT3 phosphorylation, which in turn deacetylates and dimerizes CPT2 to enhance fatty acid oxidation. Thus, an advantageous effect is suggested by the consumption of LPA that augments mitochondrial metabolic homeostasis via CDK1-SIRT3-CPT2 cascade.
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Affiliation(s)
- Lin Liu
- Department of Radiation Oncology, School of Medicine, University of California, Davis, Sacramento, CA, USA; Institute of Liver Diseases, Shuguan Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Bowen Xie
- Department of Radiation Oncology, School of Medicine, University of California, Davis, Sacramento, CA, USA
| | - Ming Fan
- Department of Radiation Oncology, School of Medicine, University of California, Davis, Sacramento, CA, USA
| | - Demet Candas-Green
- Department of Radiation Oncology, School of Medicine, University of California, Davis, Sacramento, CA, USA
| | - Joy X Jiang
- Department of Internal Medicine, Division of Gastroenterology and Hepatology, School of Medicine, University of California, Davis, Sacramento, CA, USA
| | - Ryan Wei
- Department of Radiation Oncology, School of Medicine, University of California, Davis, Sacramento, CA, USA; Lewis Katz School of Medicine, Temple University, Philadelphia, PA, USA
| | - Yinsheng Wang
- Department of Chemistry, University of California, Riverside, Riverside, CA, USA
| | - Hong-Wu Chen
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, Sacramento, CA, USA; Comprehensive Cancer Center, University of California, Davis, Sacramento, CA, USA
| | - Yiyang Hu
- Institute of Liver Diseases, Shuguan Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Jian Jian Li
- Department of Radiation Oncology, School of Medicine, University of California, Davis, Sacramento, CA, USA; Comprehensive Cancer Center, University of California, Davis, Sacramento, CA, USA.
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19
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Leung GKW, Huggins CE, Ware RS, Bonham MP. Time of day difference in postprandial glucose and insulin responses: Systematic review and meta-analysis of acute postprandial studies. Chronobiol Int 2019; 37:311-326. [DOI: 10.1080/07420528.2019.1683856] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Gloria K. W. Leung
- Department of Nutrition, Dietetics and Food, Monash University, Melbourne, Victoria, Australia
| | - Catherine E. Huggins
- Department of Nutrition, Dietetics and Food, Monash University, Melbourne, Victoria, Australia
| | - Robert S. Ware
- Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
| | - Maxine P. Bonham
- Department of Nutrition, Dietetics and Food, Monash University, Melbourne, Victoria, Australia
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20
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Melatonin and Multiple Sclerosis: From Plausible Neuropharmacological Mechanisms of Action to Experimental and Clinical Evidence. Clin Drug Investig 2019; 39:607-624. [PMID: 31054087 DOI: 10.1007/s40261-019-00793-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Multiple sclerosis (MS) is a devastating chronic autoimmune demyelinating disease of the central nervous system (CNS), thought to affect more than 2.5 million people worldwide. Regulation of the sleep-wake cycle might influence disease activity and the frequency of relapses in patients. As melatonin (or sleep hormone) involves the regulation of circadian rhythms, much attention has been paid to the management of MS symptoms with melatonin. This review describes the pharmacological mechanisms underlying the neuroprotective effects of melatonin and recent clinical evidence from MS patients. Apparent risks and benefits of melatonin therapies are also discussed. Various in vivo and clinical data presented in this up-to-date review suggest that melatonin may possibly possess a protective role against the behavioral deficits and neuropathological characteristics of MS. Multiple mechanisms of the neuroprotective effects of melatonin such as mitochondrial protection and antioxidant, anti-inflammatory, and anti-apoptotic properties, as well as its anti-demyelinating function are also discussed. A large body of evidence shows that melatonin potently regulates the immune system, demyelination, free radical generation, and inflammatory responses in neural tissue, which are mediated by multiple signal transduction cascades. In the present article, we focus on different pathways that are targeted by melatonin to prevent the development and progression of MS.
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21
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Bonham MP, Kaias E, Huggins CE, Davis R, Leung GK, Eikelis N, Shaw E, Murgia C. Effects of macronutrient manipulation on postprandial metabolic responses in overweight males with high fasting lipids during simulated shift work: A randomized crossover trial. Clin Nutr 2019; 39:369-377. [PMID: 30853262 DOI: 10.1016/j.clnu.2019.02.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 02/08/2019] [Accepted: 02/09/2019] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Meals consumed out of synchronisation with normal circadian rhythms are associated with metabolic dysregulation. Changes in macronutrient composition of meals can improve metabolic responses during the day. Therefore, we aimed to investigate whether macronutrient manipulation of meals alters postprandial glucose and lipid responses and the expression of circadian genes during the night. METHODS In a randomised crossover trial, 16 overweight males with high fasting lipids were fed isocaloric meals (2.7 MJ) at 0000 h. The meals differed primarily in total fat and total sugars content (control (8% total sugar, 5% saturated fat) vs test (16% total sugar, 26% saturated fat)). Postprandial blood samples were collected for glucose, insulin (3 h) and triglycerides (6 h) and analysed as incremental area under the curve (iAUC). RNA was extracted at 0 h, 2 h and 4 h and changes in expressions of the circadian genes clock and Per 1-3 analysed. RESULTS Postprandial glucose (p = 0.04) and insulin iAUC (p = 0.02) were significantly higher after consumption of the test meal compared to the control meal. Postprandial triglyceride iAUC was not statistically different between the two meal types (p = 0.72). No change in circadian gene expression was observed after the two meals. CONCLUSIONS Our results showed that macronutrient composition affects postprandial metabolic response at night. It emphasizes the need to consider the role and effects of night time eating, when developing metabolic disease prevention strategies for shift workers. STUDY ID NUMBER ACTRN12618001115224. WEBSITE OF TRIAL REGISTRY: http://www.anzctr.org.au/. Retrospectively registered after data collection.
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Affiliation(s)
- Maxine P Bonham
- Department of Nutrition, Dietetics and Food, Monash University, Notting Hill, Victoria, 3168, Australia.
| | - Elleni Kaias
- Department of Nutrition, Dietetics and Food, Monash University, Notting Hill, Victoria, 3168, Australia.
| | - Catherine E Huggins
- Department of Nutrition, Dietetics and Food, Monash University, Notting Hill, Victoria, 3168, Australia.
| | - Rochelle Davis
- Department of Nutrition, Dietetics and Food, Monash University, Notting Hill, Victoria, 3168, Australia.
| | - Gloria Kw Leung
- Department of Nutrition, Dietetics and Food, Monash University, Notting Hill, Victoria, 3168, Australia.
| | - Nina Eikelis
- Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, Victoria, Australia; Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia.
| | - Emma Shaw
- Department of Nutrition, Dietetics and Food, Monash University, Notting Hill, Victoria, 3168, Australia.
| | - Chiara Murgia
- Department of Nutrition, Dietetics and Food, Monash University, Notting Hill, Victoria, 3168, Australia.
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22
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Leung GK, Huggins CE, Bonham MP. Effect of meal timing on postprandial glucose responses to a low glycemic index meal: A crossover trial in healthy volunteers. Clin Nutr 2019; 38:465-471. [DOI: 10.1016/j.clnu.2017.11.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 11/06/2017] [Accepted: 11/14/2017] [Indexed: 01/17/2023]
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23
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Bonham MP, Kaias E, Zimberg I, Leung GKW, Davis R, Sletten TL, Windsor-Aubrey H, Huggins CE. Effect of Night Time Eating on Postprandial Triglyceride Metabolism in Healthy Adults: A Systematic Literature Review. J Biol Rhythms 2019; 34:119-130. [DOI: 10.1177/0748730418824214] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Eating at night time, as is frequent in shift workers, may contribute to increased cardiovascular disease (CVD) risk through a disruption in usual lipid metabolism, resulting in repeated and sustained hyperlipidemia at night. This systematic review aimed to investigate the impact of eating a meal at night compared with the same meal eaten during the day on postprandial lipemia. Six databases were searched: CINAHL Plus, Cochrane Library, EMBASE, Ovid MEDLINE, Informit, and SCOPUS. Eligible studies were original research cross-over design with a minimum fasting period of 5 h before testing preceded by a standardized control meal; measured postprandial triacylglycerol (TAG) for 5 h or greater; had meal time between 0700 h and 1600 h for day time and between 2000 h and 0400 h for night time; and had within-study test meals (food or drink) that were identical in macronutrient composition and energy. Two authors independently completed eligibility and quality assessment using the American Dietetic Association Quality Criteria Checklist for Primary Research. After removing duplicates, 4,423 articles were screened, yielding 5 studies for qualitative synthesis. All studies identified at least one parameter of the postprandial TAG response that was different as a result of meal time (e.g., the total concentration or the time course kinetics). Two studies reported a greater total TAG concentration (area under curve) at night compared with day, and 3 studies found no difference. Four studies reported that the kinetics of the postprandial time course of TAGs was different at night compared with during the day. Inconsistent reporting in the primary studies was a limitation of the review. Night eating may negatively affect postprandial lipemia and this review shows there is a need to rigorously test this using standardized methods and analysis with larger sample sizes. This is critical for informing strategies to lower CVD risk for shift workers.
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Affiliation(s)
- Maxine P. Bonham
- Department of Nutrition, Dietetics and Food, Monash University, VIC Australia
| | - Elleni Kaias
- Department of Nutrition, Dietetics and Food, Monash University, VIC Australia
| | - Iona Zimberg
- Department of Nutrition, Dietetics and Food, Monash University, VIC Australia
| | - Gloria K. W. Leung
- Department of Nutrition, Dietetics and Food, Monash University, VIC Australia
| | - Rochelle Davis
- Department of Nutrition, Dietetics and Food, Monash University, VIC Australia
| | - Tracey L. Sletten
- Monash Institute of Cognitive and Clinical Neurosciences, School of Psychological Sciences, Monash University, VIC, Australia
- Cooperative Research Centre for Alertness, Safety and Productivity, VIC, Australia
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Working in Shifts and the Metabolic Syndrome: Epidemiological Evidence and Physiopathological Mechanisms. ARS MEDICA TOMITANA 2019. [DOI: 10.2478/arsm-2018-0026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
The Metabolic syndrome (MetS) is considered as an association of the abdominal obesity, abnormal metabolism of the lipids and glucose (high level of triglycerides, low level of HDL-cholesterol and high level of glycemia) and high values of blood pressure, determined by an underlying mechanism of insulin resistance. As a result of environmental-gene interaction, MetS is associated with unhealthy nutrition, smoking, alcohol abuse, lack of physical activity, shorter sleep duration and desynchronization of the circadian rhytm caused by working in shifts. The aim of this article is to review the effects of working in shifts on the MetS through the epidemiological evidence and the perspective of the physiopathological mechanisms.
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Abstract
Last year melatonin was 60 years old, or at least its discovery was 60 years ago. The molecule itself may well be almost as old as life itself. So it is time to take yet another perspective on our understanding of its functions, effects and clinical uses. This is not a formal review-there is already a multitude of systematic reviews, narrative reviews, meta-analyses and even reviews of reviews. In view of the extraordinary variety of effects attributed to melatonin in the last 25 years, it is more of an attempt to sort out some areas where a consensus opinion exists, and where placebo controlled, randomized, clinical trials have confirmed early observations on therapeutic uses. The current upsurge of concern about the multiple health problems associated with disturbed circadian rhythms has generated interest in related therapeutic interventions, of which melatonin is one. The present text will consider the physiological role of endogenous melatonin, and the mostly pharmacological effects of exogenous treatment, on the assumption that normal circulating concentrations represent endogenous pineal production. It will concentrate mainly on the most researched, and accepted area of therapeutic use and potential use of melatonin-its undoubted ability to realign circadian rhythms and sleep-since this is the author's bias. It will touch briefly upon some other systems with prominent rhythmic attributes including certain cancers, the cardiovascular system, the entero-insular axis and metabolism together with the use of melatonin to assess circadian status. Many of the ills of the developed world relate to deranged rhythms-and everything is rhythmic unless proved otherwise.
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Meal pattern validation: associations of meal size and meal timing with glucose concentrations in a population-based cohort. Proc Nutr Soc 2019. [DOI: 10.1017/s0029665119000363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Meneses-Santos D, Buonfiglio DDC, Peliciari-Garcia RA, Ramos-Lobo AM, Souza DDN, Carpinelli AR, Carvalho CRDO, Sertie RAL, Andreotti S, Lima FB, Afeche SC, Fioretto ET, Cipolla-Neto J, Marçal AC. Chronic treatment with dexamethasone alters clock gene expression and melatonin synthesis in rat pineal gland at night. Nat Sci Sleep 2018; 10:203-215. [PMID: 30046256 PMCID: PMC6054274 DOI: 10.2147/nss.s158602] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Melatonin is a neuroendocrine hormone that regulates many functions involving energy metabolism and behavior in mammals throughout the light/dark cycle. It is considered an output signal of the central circadian clock, located in the suprachiasmatic nucleus of the hypothalamus. Melatonin synthesis can be influenced by other hormones, such as insulin and glucocorticoids in pathological conditions or during stress. Furthermore, glucocorticoids appear to modulate circadian clock genes in peripheral tissues and are associated with the onset of metabolic diseases. In the pineal gland, the modulation of melatonin synthesis by clock genes has already been demonstrated. However, few studies have shown the effects of glucocorticoids on clock genes expression in the pineal gland. RESULTS We verified that rats treated with dexamethasone (2 mg/kg body weight, intraperitoneal) for 10 consecutive days, showed hyperglycemia and pronounced hyperinsulinemia during the dark phase. Insulin sensitivity, glucose tolerance, melatonin synthesis, and enzymatic activity of arylalkylamine N-acetyltransferase, the key enzyme of melatonin synthesis, were reduced. Furthermore, we observed an increase in the expression of Bmal1, Per1, Per2, Cry1, and Cry2 in pineal glands of rats treated with dexamethasone. CONCLUSION These results show that chronic treatment with dexamethasone can modulate both melatonin synthesis and circadian clock expression during the dark phase.
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Affiliation(s)
- Daniela Meneses-Santos
- Department of Morphology, Center of Biological Sciences and Health, Federal University of Sergipe, São Cristóvão, Brazil,
| | - Daniella do Carmo Buonfiglio
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | | | - Angela Maria Ramos-Lobo
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Divanízia do Nascimento Souza
- Department of Morphology, Center of Biological Sciences and Health, Federal University of Sergipe, São Cristóvão, Brazil,
| | - Angelo Rafael Carpinelli
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | | | | | - Sandra Andreotti
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Fabio Bessa Lima
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | | | - Emerson Ticona Fioretto
- Department of Morphology, Center of Biological Sciences and Health, Federal University of Sergipe, São Cristóvão, Brazil,
| | - José Cipolla-Neto
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Anderson Carlos Marçal
- Department of Morphology, Center of Biological Sciences and Health, Federal University of Sergipe, São Cristóvão, Brazil,
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McHill AW, Hull JT, McMullan CJ, Klerman EB. Chronic Insufficient Sleep Has a Limited Impact on Circadian Rhythmicity of Subjective Hunger and Awakening Fasted Metabolic Hormones. Front Endocrinol (Lausanne) 2018; 9:319. [PMID: 29946297 PMCID: PMC6005823 DOI: 10.3389/fendo.2018.00319] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 05/28/2018] [Indexed: 01/04/2023] Open
Abstract
UNLABELLED Weight gain and obesity have reached epidemic proportions in modern society. Insufficient sleep-which is also prevalent in modern society-and eating at inappropriate circadian times have been identified as risk factors for weight gain, yet the impact of chronic insufficient sleep on the circadian timing of subjective hunger and physiologic metabolic outcomes are not well understood. We investigated how chronic insufficient sleep impacts the circadian timing of subjective hunger and fasting metabolic hormones in a 32-day in-laboratory randomized single-blind control study, with healthy younger participants (range, 20-34 years) randomized to either Control (1:2 sleep:wake ratio, 6.67 h sleep:13.33 h wake, n = 7, equivalent to 8 h of sleep per 24 h) or chronic sleep restriction (CSR, 1:3.3 sleep:wake ratio, 4.67 h sleep:15.33 h wake, n = 8, equivalent to 5.6 h of sleep per 24 h) conditions. Participants lived on a "20 h day" designed to distribute all behaviors and food intake equally across all phases of the circadian cycle over every six consecutive 20 h protocol days. During each 20 h day, participants were provided a nutritionist-designed, isocaloric diet consisting of 45-50% carbohydrate, 30-35% fat, and 15-20% protein adjusted for sex, weight, and age. Subjective non-numeric ratings of hunger were recorded before and after meals and fasting blood samples were taken within 5 min of awakening. Subjective levels of hunger and fasting concentrations of leptin, ghrelin, insulin, glucose, adiponectin, and cortisol all demonstrated circadian patterns; there were no differences, however, between CSR and Control conditions in subjective hunger ratings or any fasting hormone concentrations. These findings suggest that chronic insufficient sleep may have a limited role in altering the robust circadian profile of subjective hunger and fasted metabolic hormones. CLINICAL TRIAL REGISTRATION The study was registered as clinical trial #NCT01581125.
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Affiliation(s)
- Andrew W. McHill
- Division of Sleep and Circadian Disorders, Department of Medicine, Brigham and Women’s Hospital, Boston, MA, United States
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, United States
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, United States
- *Correspondence: Andrew W. McHill,
| | - Joseph T. Hull
- Division of Sleep and Circadian Disorders, Department of Medicine, Brigham and Women’s Hospital, Boston, MA, United States
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, United States
| | - Ciaran J. McMullan
- Renal Division, Brigham and Women’s Hospital, Boston, MA, United States
- Channing Division of Network Medicine, Brigham and Women’s Hospital, Boston, MA, United States
| | - Elizabeth B. Klerman
- Division of Sleep and Circadian Disorders, Department of Medicine, Brigham and Women’s Hospital, Boston, MA, United States
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, United States
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Grant CL, Coates AM, Dorrian J, Kennaway DJ, Wittert GA, Heilbronn LK, Pajcin M, Della Vedova C, Gupta CC, Banks S. Timing of food intake during simulated night shift impacts glucose metabolism: A controlled study. Chronobiol Int 2017. [DOI: 10.1080/07420528.2017.1335318] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Crystal L. Grant
- Centre for Sleep Research, University of South Australia, Adelaide, SA, Australia
| | - Alison M. Coates
- Alliance for Research in Exercise, Nutrition and Activity, University of South Australia, Adelaide, SA, Australia
| | - Jillian Dorrian
- Centre for Sleep Research, University of South Australia, Adelaide, SA, Australia
| | - David J. Kennaway
- Robinson Research Institute and Adelaide School of Medicine, University of Adelaide, Adelaide, SA, Australia
| | - Gary A. Wittert
- Robinson Research Institute and Adelaide School of Medicine, University of Adelaide, Adelaide, SA, Australia
- South Australian Health and Medical Research Institute, Adelaide, SA, Australia
| | - Leonie K Heilbronn
- Robinson Research Institute and Adelaide School of Medicine, University of Adelaide, Adelaide, SA, Australia
- South Australian Health and Medical Research Institute, Adelaide, SA, Australia
| | - Maja Pajcin
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA, Australia
| | - Chris Della Vedova
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA, Australia
| | - Charlotte C. Gupta
- Centre for Sleep Research, University of South Australia, Adelaide, SA, Australia
| | - Siobhan Banks
- Centre for Sleep Research, University of South Australia, Adelaide, SA, Australia
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Influences on Dietary Choices during Day versus Night Shift in Shift Workers: A Mixed Methods Study. Nutrients 2017; 9:nu9030193. [PMID: 28245625 PMCID: PMC5372856 DOI: 10.3390/nu9030193] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 02/14/2017] [Accepted: 02/20/2017] [Indexed: 01/02/2023] Open
Abstract
Shift work is associated with diet-related chronic conditions such as obesity and cardiovascular disease. This study aimed to explore factors influencing food choice and dietary intake in shift workers. A fixed mixed method study design was undertaken on a convenience sample of firefighters who continually work a rotating roster. Six focus groups (n = 41) were conducted to establish factors affecting dietary intake whilst at work. Dietary intake was assessed using repeated 24 h dietary recalls (n = 19). Interviews were audio recorded, transcribed verbatim, and interpreted using thematic analysis. Dietary data were entered into FoodWorks and analysed using Wilcoxon signed-rank test; p < 0.05 was considered significant. Thematic analysis highlighted four key themes influencing dietary intake: shift schedule; attitudes and decisions of co-workers; time and accessibility; and knowledge of the relationship between food and health. Participants reported consuming more discretionary foods and limited availability of healthy food choices on night shift. Energy intakes (kJ/day) did not differ between days that included a day or night shift but greater energy density (EDenergy, kJ/g/day) of the diet was observed on night shift compared with day shift. This study has identified a number of dietary-specific shift-related factors that may contribute to an increase in unhealthy behaviours in a shift-working population. Given the increased risk of developing chronic diseases, organisational change to support workers in this environment is warranted.
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Potter GDM, Skene DJ, Arendt J, Cade JE, Grant PJ, Hardie LJ. Circadian Rhythm and Sleep Disruption: Causes, Metabolic Consequences, and Countermeasures. Endocr Rev 2016; 37:584-608. [PMID: 27763782 PMCID: PMC5142605 DOI: 10.1210/er.2016-1083] [Citation(s) in RCA: 289] [Impact Index Per Article: 36.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Circadian (∼24-hour) timing systems pervade all kingdoms of life and temporally optimize behavior and physiology in humans. Relatively recent changes to our environments, such as the introduction of artificial lighting, can disorganize the circadian system, from the level of the molecular clocks that regulate the timing of cellular activities to the level of synchronization between our daily cycles of behavior and the solar day. Sleep/wake cycles are intertwined with the circadian system, and global trends indicate that these, too, are increasingly subject to disruption. A large proportion of the world's population is at increased risk of environmentally driven circadian rhythm and sleep disruption, and a minority of individuals are also genetically predisposed to circadian misalignment and sleep disorders. The consequences of disruption to the circadian system and sleep are profound and include myriad metabolic ramifications, some of which may be compounded by adverse effects on dietary choices. If not addressed, the deleterious effects of such disruption will continue to cause widespread health problems; therefore, implementation of the numerous behavioral and pharmaceutical interventions that can help restore circadian system alignment and enhance sleep will be important.
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Affiliation(s)
- Gregory D M Potter
- Division of Epidemiology and Biostatistics (G.D.M.P., L.J.H.), LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom; Chronobiology Section (D.J.S., J.A.), Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, United Kingdom; Nutritional Epidemiology Group (J.E.C.), School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, United Kingdom; and Division of Cardiovascular & Diabetes Research (P.J.G.), LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Debra J Skene
- Division of Epidemiology and Biostatistics (G.D.M.P., L.J.H.), LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom; Chronobiology Section (D.J.S., J.A.), Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, United Kingdom; Nutritional Epidemiology Group (J.E.C.), School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, United Kingdom; and Division of Cardiovascular & Diabetes Research (P.J.G.), LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Josephine Arendt
- Division of Epidemiology and Biostatistics (G.D.M.P., L.J.H.), LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom; Chronobiology Section (D.J.S., J.A.), Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, United Kingdom; Nutritional Epidemiology Group (J.E.C.), School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, United Kingdom; and Division of Cardiovascular & Diabetes Research (P.J.G.), LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Janet E Cade
- Division of Epidemiology and Biostatistics (G.D.M.P., L.J.H.), LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom; Chronobiology Section (D.J.S., J.A.), Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, United Kingdom; Nutritional Epidemiology Group (J.E.C.), School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, United Kingdom; and Division of Cardiovascular & Diabetes Research (P.J.G.), LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Peter J Grant
- Division of Epidemiology and Biostatistics (G.D.M.P., L.J.H.), LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom; Chronobiology Section (D.J.S., J.A.), Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, United Kingdom; Nutritional Epidemiology Group (J.E.C.), School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, United Kingdom; and Division of Cardiovascular & Diabetes Research (P.J.G.), LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Laura J Hardie
- Division of Epidemiology and Biostatistics (G.D.M.P., L.J.H.), LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom; Chronobiology Section (D.J.S., J.A.), Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, United Kingdom; Nutritional Epidemiology Group (J.E.C.), School of Food Science and Nutrition, University of Leeds, Leeds LS2 9JT, United Kingdom; and Division of Cardiovascular & Diabetes Research (P.J.G.), LIGHT Laboratories, University of Leeds, Leeds LS2 9JT, United Kingdom
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Abstract
The human circadian system anticipates and adapts to daily environmental changes to optimise behaviour according to time of day and temporally partitions incompatible physiological processes. At the helm of this system is a master clock in the suprachiasmatic nuclei (SCN) of the anterior hypothalamus. The SCN are primarily synchronised to the 24-h day by the light/dark cycle; however, feeding/fasting cycles are the primary time cues for clocks in peripheral tissues. Aligning feeding/fasting cycles with clock-regulated metabolic changes optimises metabolism, and studies of other animals suggest that feeding at inappropriate times disrupts circadian system organisation, and thereby contributes to adverse metabolic consequences and chronic disease development. 'High-fat diets' (HFD) produce particularly deleterious effects on circadian system organisation in rodents by blunting feeding/fasting cycles. Time-of-day-restricted feeding, where food availability is restricted to a period of several hours, offsets many adverse consequences of HFD in these animals; however, further evidence is required to assess whether the same is true in humans. Several nutritional compounds have robust effects on the circadian system. Caffeine, for example, can speed synchronisation to new time zones after jetlag. An appreciation of the circadian system has many implications for nutritional science and may ultimately help reduce the burden of chronic diseases.
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Singh R, Sharma S, Singh RK, Mahdi AA, Singh RK, Lee Gierke C, Cornelissen G. Effect of gender, age, diet and smoking status on chronomics of circulating plasma lipid components in healthy Indians. Clin Chim Acta 2016; 459:10-18. [PMID: 27206813 DOI: 10.1016/j.cca.2016.05.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 05/03/2016] [Accepted: 05/16/2016] [Indexed: 12/30/2022]
Abstract
BACKGROUND Circulating lipid components were studied under near-normal tropical conditions (around Lucknow) in 162 healthy volunteers - mostly medical students, staff members and members of their families (103 males and 59 females; 7 to 75y), subdivided into 4 age groups: A (7-20y; N=42), B (21-40y; N=60), C (41-60y; N=35) and D (61-75y; N=25). METHODS Blood samples were collected from each subject every 6h for 24h (4 samples). Plasma was separated and total cholesterol, high-density-lipoprotein (HDL) cholesterol, phospholipids and total lipids were measured spectrophotometrically. Data from each subject were analyzed by cosinor. We examined by multiple-analysis of variance how the MESOR (Midline Estimating Statistic Of Rhythm, a rhythm-adjusted mean) and the circadian amplitude of these variables is affected by gender, age, diet (vegetarian vs. omnivore), and smoking status. RESULTS In addition to effects of gender and age, diet and smoking were found to affect the MESOR of circulating plasma lipid components in healthy Indians residing in northern India. Age also affected the circadian amplitude of these variables. CONCLUSION These results indicate the possibility of using non-pharmacological interventions to improve a patient's metabolic profile before prescribing medication under near normal tropical conditions. They also add information that may help refine cut-off values in the light of factors shown here to affect blood lipids.
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Affiliation(s)
- Ranjana Singh
- Biochemistry Department, King George's Medical University, Lucknow 226003, India
| | - Sumita Sharma
- Biochemistry Department, Sgrr Institute of Medical & Health Sciences, Dehradun 248001, India
| | - Rajesh K Singh
- Biochemistry Department, T S Misra Medical College and Hospital, Lucknow 226008, India
| | - Abbas A Mahdi
- Biochemistry Department, King George's Medical University, Lucknow 226003, India
| | - Raj K Singh
- Biochemistry Department, T S Misra Medical College and Hospital, Lucknow 226008, India
| | - Cathy Lee Gierke
- Halberg Chronobiology Center, University Of Minnesota, Minneapolis, MN 55455, USA
| | - Germaine Cornelissen
- Halberg Chronobiology Center, University Of Minnesota, Minneapolis, MN 55455, USA.
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Morris CJ, Purvis TE, Mistretta J, Scheer FAJL. Effects of the Internal Circadian System and Circadian Misalignment on Glucose Tolerance in Chronic Shift Workers. J Clin Endocrinol Metab 2016; 101:1066-74. [PMID: 26771705 PMCID: PMC4803172 DOI: 10.1210/jc.2015-3924] [Citation(s) in RCA: 132] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
CONTEXT Shift work is a risk factor for diabetes. The separate effects of the endogenous circadian system and circadian misalignment (ie, misalignment between the central circadian pacemaker and 24-hour environmental/behavioral rhythms such as the light/dark and feeding/fasting cycles) on glucose tolerance in shift workers are unknown. OBJECTIVE The objective of the study was to test the hypothesis that the endogenous circadian system and circadian misalignment separately affect glucose tolerance in shift workers, both independently from behavioral cycle effects. DESIGN A randomized, crossover study with two 3-day laboratory visits. SETTING Center for Clinical Investigation at Brigham and Women's Hospital. PATIENTS Healthy chronic shift workers. INTERVENTION The intervention included simulated night work comprised of 12-hour inverted behavioral and environmental cycles (circadian misalignment) or simulated day work (circadian alignment). MAIN OUTCOME MEASURES Postprandial glucose and insulin responses to identical meals given at 8:00 am and 8:00 pm in both protocols. RESULTS Postprandial glucose was 6.5% higher at 8:00 pm than 8:00 am (circadian phase effect), independent of behavioral effects (P = .0041). Circadian misalignment increased postprandial glucose by 5.6%, independent of behavioral and circadian effects (P = .0042). These variations in glucose tolerance appeared to be explained, at least in part, by different insulin mechanisms: during the biological evening by decreased pancreatic β-cell function (18% lower early and late phase insulin; both P ≤ .011) and during circadian misalignment presumably by decreased insulin sensitivity (elevated postprandial glucose despite 10% higher late phase insulin; P = .015) without change in early-phase insulin (P = .38). CONCLUSIONS Internal circadian time affects glucose tolerance in shift workers. Separately, circadian misalignment reduces glucose tolerance in shift workers, providing a mechanism to help explain the increased diabetes risk in shift workers.
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Affiliation(s)
- Christopher J Morris
- Medical Chronobiology Program (C.J.M., T.E.P., J.M., F.A.J.L.S.), Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, Massachusetts 02115; and Division of Sleep Medicine (C.J.M., F.A.J.L.S.), Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115
| | - Taylor E Purvis
- Medical Chronobiology Program (C.J.M., T.E.P., J.M., F.A.J.L.S.), Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, Massachusetts 02115; and Division of Sleep Medicine (C.J.M., F.A.J.L.S.), Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115
| | - Joseph Mistretta
- Medical Chronobiology Program (C.J.M., T.E.P., J.M., F.A.J.L.S.), Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, Massachusetts 02115; and Division of Sleep Medicine (C.J.M., F.A.J.L.S.), Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115
| | - Frank A J L Scheer
- Medical Chronobiology Program (C.J.M., T.E.P., J.M., F.A.J.L.S.), Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, Massachusetts 02115; and Division of Sleep Medicine (C.J.M., F.A.J.L.S.), Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115
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Smith J, Fahrenkrug J, Jørgensen HL, Christoffersen C, Goetze JP. Diurnal gene expression of lipolytic natriuretic peptide receptors in white adipose tissue. Endocr Connect 2015; 4:206-14. [PMID: 26286623 PMCID: PMC4566841 DOI: 10.1530/ec-15-0074] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 08/18/2015] [Indexed: 01/01/2023]
Abstract
Disruption of the circadian rhythm can lead to obesity and cardiovascular disease. In white adipose tissue, activation of the natriuretic peptide receptors (NPRs) stimulates lipolysis. We have previously shown that natriuretic peptides are expressed in a circadian manner in the heart, but the temporal expression profile of their cognate receptors has not been examined in white adipose tissue. We therefore collected peri-renal white adipose tissue and serum from WT mice. Tissue mRNA contents of NPRs - NPR-A and NPR-C, the clock genes Per1 and Bmal1, and transcripts involved in lipid metabolism were quantified at 4-h intervals: in the diurnal study, mice were exposed to a period of 12 h light followed by 12 h darkness (n=52). In the circadian study, mice were kept in darkness for 24 h (n=47). Concomitant serum concentrations of free fatty acids, glycerol, triglycerides (TGs), and insulin were measured. Per1 and Bmal1 mRNA contents showed reciprocal circadian profiles (P<0.0001). NPR-A mRNA contents followed a temporal pattern (P=0.01), peaking in the dark (active) period. In contrast, NPR-C mRNA was expressed in an antiphase manner with nadir in the active period (P=0.007). TG concentrations in serum peaked in the active dark period (P=0.003). In conclusion, NPR-A and NPR-C gene expression is associated with the expression of clock genes in white adipose tissue. The reciprocal expression may thus contribute to regulate lipolysis and energy homeostasis in a diurnal manner.
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Affiliation(s)
- Julie Smith
- Department of Clinical Biochemistry (KB3014) Rigshospitalet, University of Copenhagen, 9 Blegdamsvej, DK-2100 Copenhagen, Denmark Department of Technology Faculty of Health and Technology, Metropolitan University College, Copenhagen, Denmark Department of Clinical Biochemistry Faculty of Health Sciences, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark Department of Biomedical Sciences Copenhagen University, Copenhagen, Denmark Department of Clinical Medicine Aarhus University, Aarhus, Denmark
| | - Jan Fahrenkrug
- Department of Clinical Biochemistry (KB3014) Rigshospitalet, University of Copenhagen, 9 Blegdamsvej, DK-2100 Copenhagen, Denmark Department of Technology Faculty of Health and Technology, Metropolitan University College, Copenhagen, Denmark Department of Clinical Biochemistry Faculty of Health Sciences, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark Department of Biomedical Sciences Copenhagen University, Copenhagen, Denmark Department of Clinical Medicine Aarhus University, Aarhus, Denmark
| | - Henrik L Jørgensen
- Department of Clinical Biochemistry (KB3014) Rigshospitalet, University of Copenhagen, 9 Blegdamsvej, DK-2100 Copenhagen, Denmark Department of Technology Faculty of Health and Technology, Metropolitan University College, Copenhagen, Denmark Department of Clinical Biochemistry Faculty of Health Sciences, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark Department of Biomedical Sciences Copenhagen University, Copenhagen, Denmark Department of Clinical Medicine Aarhus University, Aarhus, Denmark
| | - Christina Christoffersen
- Department of Clinical Biochemistry (KB3014) Rigshospitalet, University of Copenhagen, 9 Blegdamsvej, DK-2100 Copenhagen, Denmark Department of Technology Faculty of Health and Technology, Metropolitan University College, Copenhagen, Denmark Department of Clinical Biochemistry Faculty of Health Sciences, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark Department of Biomedical Sciences Copenhagen University, Copenhagen, Denmark Department of Clinical Medicine Aarhus University, Aarhus, Denmark Department of Clinical Biochemistry (KB3014) Rigshospitalet, University of Copenhagen, 9 Blegdamsvej, DK-2100 Copenhagen, Denmark Department of Technology Faculty of Health and Technology, Metropolitan University College, Copenhagen, Denmark Department of Clinical Biochemistry Faculty of Health Sciences, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark Department of Biomedical Sciences Copenhagen University, Copenhagen, Denmark Department of Clinical Medicine Aarhus University, Aarhus, Denmark
| | - Jens P Goetze
- Department of Clinical Biochemistry (KB3014) Rigshospitalet, University of Copenhagen, 9 Blegdamsvej, DK-2100 Copenhagen, Denmark Department of Technology Faculty of Health and Technology, Metropolitan University College, Copenhagen, Denmark Department of Clinical Biochemistry Faculty of Health Sciences, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark Department of Biomedical Sciences Copenhagen University, Copenhagen, Denmark Department of Clinical Medicine Aarhus University, Aarhus, Denmark Department of Clinical Biochemistry (KB3014) Rigshospitalet, University of Copenhagen, 9 Blegdamsvej, DK-2100 Copenhagen, Denmark Department of Technology Faculty of Health and Technology, Metropolitan University College, Copenhagen, Denmark Department of Clinical Biochemistry Faculty of Health Sciences, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark Department of Biomedical Sciences Copenhagen University, Copenhagen, Denmark Department of Clinical Medicine Aarhus University, Aarhus, Denmark
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Eckel RH, Depner CM, Perreault L, Markwald RR, Smith MR, McHill AW, Higgins J, Melanson EL, Wright KP. Morning Circadian Misalignment during Short Sleep Duration Impacts Insulin Sensitivity. Curr Biol 2015; 25:3004-10. [PMID: 26549253 DOI: 10.1016/j.cub.2015.10.011] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 09/30/2015] [Accepted: 10/05/2015] [Indexed: 12/19/2022]
Abstract
Short sleep duration and circadian misalignment are hypothesized to causally contribute to health problems including obesity, diabetes, metabolic syndrome, heart disease, mood disorders, cognitive impairment, and accidents. Here, we investigated the influence of morning circadian misalignment induced by an imposed short nighttime sleep schedule on impaired insulin sensitivity, a precursor to diabetes. Imposed short sleep duration resulted in morning wakefulness occurring during the biological night (i.e., circadian misalignment)-a time when endogenous melatonin levels were still high indicating the internal circadian clock was still promoting sleep and related functions. We show the longer melatonin levels remained high after wake time, insulin sensitivity worsened. Overall, we find a simulated 5-day work week of 5-hr-per-night sleep opportunities and ad libitum food intake resulted in ∼20% reduced oral and intravenous insulin sensitivity in otherwise healthy men and women. Reduced insulin sensitivity was compensated by an increased insulin response to glucose, which may reflect an initial physiological adaptation to maintain normal blood sugar levels during sleep loss. Furthermore, we find that transitioning from the imposed short sleep schedule to 9-hr sleep opportunities for 3 days restored oral insulin sensitivity to baseline, but 5 days with 9-hr sleep opportunities was insufficient to restore intravenous insulin sensitivity to baseline. These findings indicate morning wakefulness and eating during the biological night is a novel mechanism by which short sleep duration contributes to metabolic dysregulation and suggests food intake during the biological night may contribute to other health problems associated with short sleep duration.
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Affiliation(s)
- Robert H Eckel
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Christopher M Depner
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder CO, 80309, USA
| | - Leigh Perreault
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Rachel R Markwald
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder CO, 80309, USA
| | - Mark R Smith
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder CO, 80309, USA
| | - Andrew W McHill
- Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder CO, 80309, USA
| | - Janine Higgins
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Edward L Melanson
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Division of Geriatric Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Kenneth P Wright
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Sleep and Chronobiology Laboratory, Department of Integrative Physiology, University of Colorado Boulder, Boulder CO, 80309, USA.
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Tranel HR, Schroder EA, England J, Black WS, Bush H, Hughes ME, Esser KA, Clasey JL. Physical activity, and not fat mass is a primary predictor of circadian parameters in young men. Chronobiol Int 2015; 32:832-41. [PMID: 26101893 DOI: 10.3109/07420528.2015.1043011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Circadian rhythms are ≈24 h oscillations in physiology and behavior, and disruptions have been shown to have negative effects on health. Wrist skin temperature has been used by several groups as a valid method of assessing circadian rhythms in humans. We tested the hypothesis that circadian temperature amplitude (TempAmp) and stability (TempStab) would significantly differ among groups of healthy young men of varying adiposities, and that we could identify physiological and behavioral measures that were significantly associated with these temperature parameters. Wrist skin temperatures taken at 10 min intervals for 7 consecutive days were determined in 18 optimal (OGroup), 20 fair (FGroup) and 21 poor (PGroup) %Fat grouped young men and subsequently analyzed using available validated software. Body composition, cardiorespiratory fitness, actigraphy, daily nutritional and sleep data, and fasting lipid, insulin and glucose concentration measures were also determined. Significant changes in TempAmp and TempStab parameters in subjects with a single metabolic syndrome (MetS) risk factor compared to those with no MetS factors was observed. In addition, stepwise multivariate regression analyses showed that 50% of the variance in TempAmp was explained by actigraphy (mean steps taken per day; MSTPD), cardiorespiratory fitness, and late night eating per week (#LNE); and 57% in TempStab by MSTPD, time spent in moderate-to-vigorous activity per day, fat mass, and #LNE. Overwhelmingly, physical activity was the most important measure associated with the differences in circadian rhythm parameters. Further research is warranted to determine the effects of increasing the amount and timing of physical activity on the status of the circadian system in a variety of populations.
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Endogenous circadian system and circadian misalignment impact glucose tolerance via separate mechanisms in humans. Proc Natl Acad Sci U S A 2015; 112:E2225-34. [PMID: 25870289 DOI: 10.1073/pnas.1418955112] [Citation(s) in RCA: 287] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Glucose tolerance is lower in the evening and at night than in the morning. However, the relative contribution of the circadian system vs. the behavioral cycle (including the sleep/wake and fasting/feeding cycles) is unclear. Furthermore, although shift work is a diabetes risk factor, the separate impact on glucose tolerance of the behavioral cycle, circadian phase, and circadian disruption (i.e., misalignment between the central circadian pacemaker and the behavioral cycle) has not been systematically studied. Here we show--by using two 8-d laboratory protocols--in healthy adults that the circadian system and circadian misalignment have distinct influences on glucose tolerance, both separate from the behavioral cycle. First, postprandial glucose was 17% higher (i.e., lower glucose tolerance) in the biological evening (8:00 PM) than morning (8:00 AM; i.e., a circadian phase effect), independent of the behavioral cycle effect. Second, circadian misalignment itself (12-h behavioral cycle inversion) increased postprandial glucose by 6%. Third, these variations in glucose tolerance appeared to be explained, at least in part, by different mechanisms: during the biological evening by decreased pancreatic β-cell function (27% lower early-phase insulin) and during circadian misalignment presumably by decreased insulin sensitivity (elevated postprandial glucose despite 14% higher late-phase insulin) without change in early-phase insulin. We explored possible contributing factors, including changes in polysomnographic sleep and 24-h hormonal profiles. We demonstrate that the circadian system importantly contributes to the reduced glucose tolerance observed in the evening compared with the morning. Separately, circadian misalignment reduces glucose tolerance, providing a mechanism to help explain the increased diabetes risk in shift workers.
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Abstract
Plasma levels of triacylglycerols and diacylglycerols, the lipoproteins that transport them, and proteins involved in their absorption from the intestinal lumen fluctuate in a circadian manner. These changes are likely controlled by clock genes expressed in the intestine that are probably synchronized by neuronal and humoral signals from the suprachiasmatic nuclei, which constitute a master clock entrained by light signals from the eyes and from the environment, e.g., food availability. Acute changes in circadian rhythms--e.g., due to nonsynchronous work schedules or a transcontinental flight--may trigger intestinal discomfort. Chronic disruptions in circadian control mechanisms may predispose the individual to irritable bowel syndrome, gastroesophageal reflux disease, and peptic ulcer disease. A more detailed understanding of the molecular mechanisms underlying temporal changes in intestinal activity might allow us to identify novel targets for developing therapeutic approaches to these disorders.
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Affiliation(s)
- M Mahmood Hussain
- Departments of Cell Biology and Pediatrics, SUNY Downstate Medical Center, Brooklyn, New York 11203, and Virginia New York Harbor Healthcare System, Brooklyn, New York 11209;
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Gnocchi D, Pedrelli M, Hurt-Camejo E, Parini P. Lipids around the Clock: Focus on Circadian Rhythms and Lipid Metabolism. BIOLOGY 2015; 4:104-32. [PMID: 25665169 PMCID: PMC4381220 DOI: 10.3390/biology4010104] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 01/28/2015] [Indexed: 12/24/2022]
Abstract
Disorders of lipid and lipoprotein metabolism and transport are responsible for the development of a large spectrum of pathologies, ranging from cardiovascular diseases, to metabolic syndrome, even to tumour development. Recently, a deeper knowledge of the molecular mechanisms that control our biological clock and circadian rhythms has been achieved. From these studies it has clearly emerged how the molecular clock tightly regulates every aspect of our lives, including our metabolism. This review analyses the organisation and functioning of the circadian clock and its relevance in the regulation of physiological processes. We also describe metabolism and transport of lipids and lipoproteins as an essential aspect for our health, and we will focus on how the circadian clock and lipid metabolism are greatly interconnected. Finally, we discuss how a deeper knowledge of this relationship might be useful to improve the recent spread of metabolic diseases.
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Affiliation(s)
- Davide Gnocchi
- Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet at Karolinska University Hospital Huddinge, Stockholm, 14186, Sweden.
| | - Matteo Pedrelli
- Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet at Karolinska University Hospital Huddinge, Stockholm, 14186, Sweden.
- Strategy and Externalization, CVMD iMED, AstraZeneca, R&D, Mölndal, SE-431 83, Sweden.
| | - Eva Hurt-Camejo
- Strategy and Externalization, CVMD iMED, AstraZeneca, R&D, Mölndal, SE-431 83, Sweden.
| | - Paolo Parini
- Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet at Karolinska University Hospital Huddinge, Stockholm, 14186, Sweden.
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Effects of sequential feeding with low- and high-protein diets on growth performances and plasma metabolite levels in geese. Animal 2015; 9:952-7. [PMID: 25556532 DOI: 10.1017/s1751731114003267] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
This study was conducted by two trials to investigate effects of sequential feeding with low- and high-protein diets on growth traits and plasma metabolites in geese. In Trial I, the effect of sequential feeding under time-restricted feeding system was investigated. Seventy-two White Roman goslings were randomly allotted into either sequential feeding (S1) or control feeding (C1) group. All goslings were fed for 1 h at morning and at evening, respectively, from 2 to 8 weeks of age. S1 group was offered 13% CP diet at morning and 19% CP diet at evening. C1 group was offered the same diet (16% CP; mixed equally with the two diets mentioned above) at both morning and evening. Blood samples were hourly collected for 4 h after feeding at both morning and evening for the determination of the postprandial plasma levels of glucose, triacylglycerol and uric acid at the end of experiment. Results showed that BW, average daily gain (ADG), and daily feed intake (FI) were not different between groups, but the feed efficiency (FE) in S1 group was significantly higher than that in C1 group (P<0.05). The areas under curve (AUC) of plasma postprandial levels of glucose, triacylglycerol and uric acid were not affected by treatment, but the AUC of triacylglycerol and uric acid in morning were lower than those in evening (P<0.05). In Trial II, the effect of sequential feeding under ad libitum feeding system was investigated. Twenty-four goslings were randomly allotted into either sequential feeding (S2) or control feeding (C2) group. Diets were altered at 0600 and 1800 h, respectively, and geese were fed ad libitum from 4 to 8 weeks of age. S2 group was offered 14% CP diet at morning and 20% CP diet at evening. C2 group was supplied the same diet (mixed with the two diets according to the ratio of diets consumed by S2 group on the preceded day) at both morning and evening. Results showed that the ADG in S2 group was higher than those in C2 group (P<0.05). Summarized data from both trials showed that sequential feeding improves daily gain and FE in growing geese.
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Hampton SM, Johnston JD. Probing the diurnal regulation of glycemic control. J Diabetes Complications 2014; 28:751-2. [PMID: 25161099 DOI: 10.1016/j.jdiacomp.2014.07.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 07/18/2014] [Indexed: 01/02/2023]
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Sonnier T, Rood J, Gimble JM, Peterson CM. Glycemic control is impaired in the evening in prediabetes through multiple diurnal rhythms. J Diabetes Complications 2014; 28:836-43. [PMID: 24835190 DOI: 10.1016/j.jdiacomp.2014.04.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 03/11/2014] [Accepted: 04/01/2014] [Indexed: 01/12/2023]
Abstract
AIMS Recent studies suggest that circadian rhythms regulate glucose metabolism, weight loss, and even drug efficacy. Moreover, molecules targeted at the circadian clock show promise in treating metabolic disease. Therefore, this study set out to better characterize interactions among diurnal rhythms in prediabetes. METHODS Ten subjects with prediabetes completed oral glucose tolerance tests at 0700h and 1900h on the same day. Lipids and hormones were also measured. RESULTS Two-hour and three-hour glucose tolerances were worse in the evening by 40±52mg/dl (p=0.02) and 62±46mg/dl (p=0.001), respectively. These impairments were explained by lower insulin sensitivity (OGIS; 5.14±1.02 vs. 4.74±0.77mg/kg/min; p=0.03) and 2-hour AUC insulin levels (87.4±37.6 vs. 69.8±40.2mU∙hr/l; p=0.02) in the evening. Intriguingly, more insulin resistant subjects had weaker rhythms in insulin sensitivity (r=-0.66; p=0.04) but enhanced rhythms in insulin (r=-0.67; p=0.03) and cortisol (r=-0.78; p=0.008) levels. Importantly, the rhythms in cortisol primarily but also insulin sensitivity drove the declines in evening glucose tolerance (r=0.86; p=0.002). CONCLUSIONS Glycemic control is dramatically impaired in the evening in people with prediabetes, particularly when the cortisol rhythm is weak, but is unrelated to the rhythm in insulin levels. Therefore, food intake at dinnertime may need to be curbed in prediabetes.
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Affiliation(s)
- Tance Sonnier
- Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA 70808, USA
| | - Jennifer Rood
- Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA 70808, USA
| | - Jeffrey M Gimble
- Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA 70808, USA; Center for Stem Cell Research and Regenerative Medicine, Tulane University School of Medicine, New Orleans, LA 70112, USA; LaCell LLC, New Orleans, LA 70112, USA
| | - Courtney M Peterson
- Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA 70808, USA.
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Resveratrol- and melatonin-abated ovariectomy and fructose diet–induced obesity and metabolic alterations in female rats. Menopause 2014; 21:876-85. [DOI: 10.1097/gme.0000000000000187] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Abstract
There is emerging evidence in the literature to suggest that disruption of the normal circadian rhythm (sleep-wake cycle signalling) is a potential risk factor to explain the increased incidence of metabolic syndrome. Over the last century, obesity, diabetes and other components of metabolic syndrome have been on the rise. On the other hand, the amount of sleep has decreased from an average of 6-8 h per night. Furthermore, the quality of sleep has declined with more individuals voluntarily decreasing their amount of sleep to work or enjoy leisure activities. Over the last decade, researchers have examined the relationship between disruption in human circadian system and the emergence of symptoms related to metabolic syndrome. Indeed, epidemiological studies suggest a relation between sleep duration and diabetes and obesity. Moreover, experimental animal and human studies suggest such a relation. These studies propose optimum sleep duration of 7-8 h per night to avoid circadian rhythm disruption and suggest that sleep disturbance, whether iatrogenic or disease-related, should be considered as a risk factor for metabolic syndrome, and be addressed. This field is in its infancy and further understanding of specific pathophysiological pathways of circadian desynchronisation will help in developing novel preventive and therapeutic strategies.
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Affiliation(s)
- Mae Sheikh-Ali
- Department of Medicine, University of Florida College of Medicine, Jacksonville, USA
| | - Jaisri Maharaj
- Department of Medicine, University of Florida College of Medicine, Jacksonville, USA
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Gooley JJ, Chua ECP. Diurnal regulation of lipid metabolism and applications of circadian lipidomics. J Genet Genomics 2014; 41:231-50. [PMID: 24894351 DOI: 10.1016/j.jgg.2014.04.001] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Revised: 04/10/2014] [Accepted: 04/10/2014] [Indexed: 02/04/2023]
Abstract
The circadian timing system plays a key role in orchestrating lipid metabolism. In concert with the solar cycle, the circadian system ensures that daily rhythms in lipid absorption, storage, and transport are temporally coordinated with rest-activity and feeding cycles. At the cellular level, genes involved in lipid synthesis and fatty acid oxidation are rhythmically activated and repressed by core clock proteins in a tissue-specific manner. Consequently, loss of clock gene function or misalignment of circadian rhythms with feeding cycles (e.g., in shift work) results in impaired lipid homeostasis. Herein, we review recent progress in circadian rhythms research using lipidomics, i.e., large-scale profiling of lipid metabolites, to characterize circadian-regulated lipid pathways in mammals. In mice, novel regulatory circuits involved in fatty acid metabolism have been identified in adipose tissue, liver, and muscle. Extensive diversity in circadian regulation of plasma lipids has also been revealed in humans using lipidomics and other metabolomics approaches. In future studies, lipidomics platforms will be increasingly used to better understand the effects of genetic variation, shift work, food intake, and drugs on circadian-regulated lipid pathways and metabolic health.
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Affiliation(s)
- Joshua J Gooley
- Program in Neuroscience and Behavioral Disorders, Duke-NUS Graduate Medical School, Singapore 169857, Singapore; Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston 02115, USA; Division of Sleep Medicine, Harvard Medical School, Boston 02115, USA.
| | - Eric Chern-Pin Chua
- Program in Neuroscience and Behavioral Disorders, Duke-NUS Graduate Medical School, Singapore 169857, Singapore
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Abstract
Circadian rhythms act to optimise many aspects of our biology and thereby ensure that physiological processes are occurring at the most appropriate time. The importance of this temporal control is demonstrated by the strong associations between circadian disruption, morbidity and disease pathology. There is now a wealth of evidence linking the circadian timing system to metabolic physiology and nutrition. Relationships between these processes are often reciprocal, such that the circadian system drives temporal changes in metabolic pathways and changes in metabolic/nutritional status alter core molecular components of circadian rhythms. Examples of metabolic rhythms include daily changes in glucose homeostasis, insulin sensitivity and postprandial response. Time of day alters lipid and glucose profiles following individual meals whereas, over a longer time scale, meal timing regulates adiposity and body weight; these changes may occur via the ability of timed feeding to synchronise local circadian rhythms in metabolically active tissues. Much of the work in this research field has utilised animal and cellular model systems. Although these studies are highly informative and persuasive, there is a largely unmet need to translate basic biological data to humans. The results of such translational studies may open up possibilities for using timed dietary manipulations to help restore circadian synchrony and downstream physiology. Given the large number of individuals with disrupted rhythms due to, for example, shift work, jet-lag, sleep disorders and blindness, such dietary manipulations could provide widespread improvements in health and also economic performance.
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Extensive diversity in circadian regulation of plasma lipids and evidence for different circadian metabolic phenotypes in humans. Proc Natl Acad Sci U S A 2013; 110:14468-73. [PMID: 23946426 DOI: 10.1073/pnas.1222647110] [Citation(s) in RCA: 159] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The circadian system regulates daily rhythms in lipid metabolism and adipose tissue function. Although disruption of circadian clock function is associated with negative cardiometabolic end points, very little is known about interindividual variation in circadian-regulated metabolic pathways. Here, we used targeted lipidomics-based approaches to profile the time course of 263 lipids in blood plasma in 20 healthy individuals. Over a span of 28 h, blood was collected every 4 h and plasma lipids were analyzed by HPLC/MS. Across subjects, about 13% of lipid metabolites showed circadian variation. Rhythmicity spanned all metabolite classes examined, suggesting widespread circadian control of lipid-mediated energy storage, transport, and signaling. Intersubject agreement for lipids identified as rhythmic was only about 20%, however, and the timing of lipid rhythms ranged up to 12 h apart between individuals. Healthy subjects therefore showed substantial variation in the timing and strength of rhythms across different lipid species. Strong interindividual differences were also observed for rhythms of blood glucose and insulin, but not cortisol. Using consensus clustering with iterative feature selection, subjects clustered into different groups based on strength of rhythmicity for a subset of triglycerides and phosphatidylcholines, suggesting that there are different circadian metabolic phenotypes in the general population. These results have potential implications for lipid metabolism disorders linked to circadian clock disruption.
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50
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Dumont M, Lanctôt V, Cadieux-Viau R, Paquet J. Melatonin production and light exposure of rotating night workers. Chronobiol Int 2012; 29:203-10. [PMID: 22324558 DOI: 10.3109/07420528.2011.647177] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Decreased melatonin production, due to acute suppression of pineal melatonin secretion by light exposure during night work, has been suggested to underlie higher cancer risks associated with prolonged experience of night work. However, the association between light exposure and melatonin production has never been measured in the field. In this study, 24-h melatonin production and ambulatory light exposure were assessed during both night-shift and day/evening-shift periods in 13 full-time rotating shiftworkers. Melatonin production was estimated with the excretion of urinary 6-sulfatoxymelatonin (aMT6s), and light exposure was measured with an ambulatory photometer. There was no difference in total 24-h aMT6s excretion between the two work periods. The night-shift period was characterized by a desynchrony between melatonin and sleep-wake rhythms, as shown by higher melatonin production during work and lower melatonin production during sleep when working night shifts than when working day/evening shifts. Light exposure during night work showed no correlation with aMT6s excreted during the night of work (p > .5), or with the difference in 24-h aMT6s excretion between the two work periods (p > .1). However, light exposure during night work was negatively correlated with total 24-h aMT6s excretion over the entire night-shift period (p < .01). In conclusion, there was no evidence of direct melatonin suppression during night work in this population. However, higher levels of light exposure during night work may have decreased total melatonin production, possibly by initiating re-entrainment and causing internal desynchrony. This interpretation is consistent with the proposition that circadian disruption, of which decreased melatonin production is only one of the adverse consequences, could be the mediator between night shiftwork and cancer risks.
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Affiliation(s)
- Marie Dumont
- Chronobiology Laboratory, Center for Advanced Research in Sleep Medicine, Sacre-Coeur Hospital of Montreal, Montreal, Quebec, Canada.
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