Joanna E Wrede1,2, Jonas Mengel-From3,4, Dedra Buchwald5,6, Michael V Vitiello7,8, Michael Bamshad2, Carolyn Noonan5,6, Lene Christiansen3, Kaare Christensen3,4,9, Nathaniel F Watson1,6,8. 1. Department of Neurology, University of Washington, Seattle, WA. 2. Department of Pediatrics, University of Washington, Seattle, WA. 3. The Danish Aging Research Center and The Danish Twin Registry, Epidemiology Unit, Institute of Public Health, University of Southern Denmark, Odense, Denmark. 4. Department of Clinical Genetics, Odense University Hospital, Odense, Denmark. 5. Departments of Epidemiology and Medicine, University of Washington, Seattle, WA. 6. University of Washington Twin Registry, Seattle, WA. 7. Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA. 8. Center for Research on the Management of Sleep Disturbances, University of Washington, Seattle, WA. 9. Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark.
Abstract
STUDY OBJECTIVES: Mitochondrial DNA (mtDNA) copy number is an important component of mitochondrial function and varies with age, disease, and environmental factors. We aimed to determine whether mtDNA copy number varies with habitual differences in sleep duration within pairs of monozygotic twins. SETTING: Academic clinical research center. PARTICIPANTS: 15 sleep duration discordant monozygotic twin pairs (30 twins, 80% female; mean age 42.1 years [SD 15.0]). DESIGN: Sleep duration was phenotyped with wrist actigraphy. Each twin pair included a "normal" (7-9 h/24) and "short" (< 7 h/24) sleeping twin. Fasting peripheral blood leukocyte DNA was assessed for mtDNA copy number via the n-fold difference between qPCR measured mtDNA and nuclear DNA creating an mtDNA measure without absolute units. We used generalized estimating equation linear regression models accounting for the correlated data structure to assess within-pair effects of sleep duration on mtDNA copy number. MEASUREMENTS AND RESULTS: Mean within-pair sleep duration difference per 24 hours was 94.3 minutes (SD 62.6 min). We found reduced sleep duration (β = 0.06; 95% CI 0.004, 0.12; P < 0.05) and sleep efficiency (β = 0.51; 95% CI 0.06, 0.95; P < 0.05) were significantly associated with reduced mtDNA copy number within twin pairs. Thus every 1-minute decrease in actigraphy-defined sleep duration was associated with a decrease in mtDNA copy number of 0.06. Likewise, a 1% decrease in actigraphy-defined sleep efficiency was associated with a decrease in mtDNA copy number of 0.51. CONCLUSIONS: Reduced sleep duration and sleep efficiency were associated with reduced mitochondrial DNA copy number in sleep duration discordant monozygotic twins offering a potential mechanism whereby short sleep impairs health and longevity through mitochondrial stress.
STUDY OBJECTIVES: Mitochondrial DNA (mtDNA) copy number is an important component of mitochondrial function and varies with age, disease, and environmental factors. We aimed to determine whether mtDNA copy number varies with habitual differences in sleep duration within pairs of monozygotic twins. SETTING: Academic clinical research center. PARTICIPANTS: 15 sleep duration discordant monozygotic twin pairs (30 twins, 80% female; mean age 42.1 years [SD 15.0]). DESIGN: Sleep duration was phenotyped with wrist actigraphy. Each twin pair included a "normal" (7-9 h/24) and "short" (< 7 h/24) sleeping twin. Fasting peripheral blood leukocyte DNA was assessed for mtDNA copy number via the n-fold difference between qPCR measured mtDNA and nuclear DNA creating an mtDNA measure without absolute units. We used generalized estimating equation linear regression models accounting for the correlated data structure to assess within-pair effects of sleep duration on mtDNA copy number. MEASUREMENTS AND RESULTS: Mean within-pair sleep duration difference per 24 hours was 94.3 minutes (SD 62.6 min). We found reduced sleep duration (β = 0.06; 95% CI 0.004, 0.12; P < 0.05) and sleep efficiency (β = 0.51; 95% CI 0.06, 0.95; P < 0.05) were significantly associated with reduced mtDNA copy number within twin pairs. Thus every 1-minute decrease in actigraphy-defined sleep duration was associated with a decrease in mtDNA copy number of 0.06. Likewise, a 1% decrease in actigraphy-defined sleep efficiency was associated with a decrease in mtDNA copy number of 0.51. CONCLUSIONS: Reduced sleep duration and sleep efficiency were associated with reduced mitochondrial DNA copy number in sleep duration discordant monozygotic twins offering a potential mechanism whereby short sleep impairs health and longevity through mitochondrial stress.
Authors: H Dean Hosgood; Chin-San Liu; Nathaniel Rothman; Stephanie J Weinstein; Matthew R Bonner; Min Shen; Unhee Lim; Jarmo Virtamo; Wen-ling Cheng; Demetrius Albanes; Qing Lan Journal: Carcinogenesis Date: 2010-02-22 Impact factor: 4.944
Authors: Jiu-Chiuan Chen; Robert L Brunner; Hong Ren; Sylvia Wassertheil-Smoller; Joseph C Larson; Douglas W Levine; Matthew Allison; Michelle J Naughton; Marcia L Stefanick Journal: Stroke Date: 2008-07-17 Impact factor: 7.914