Leukocyte Telomere Length in Healthy Caucasian and African-American Adolescents: Relationships with Race, Sex, Adiposity, Adipokines, and Physical Activity

Abstract

Objectives-To examine the relations of race, sex, adiposity, adipokines and physical activity to telomere length in adolescents.Study design-Leukocyte telomere length (T/S ratio) was assessed cross-sectionally in 667 adolescents (aged 14-18 years, 48% blacks, 51% girls) using a quantitative PCR method. Generalized Estimating Equations analyses were performed.Results-Black adolescents had longer telomeres than white adolescents (age and sex adjusted T/S ratio ± SE: 1.32 ± 0.01 vs. 1.27 ± 0.01, p=0.014) and girls had longer telomeres than boys (age and race adjusted T/S ratio ± SE: 1.31 ± 0.01 vs. 1.27 ± 0.01, p=0.007). None of the adiposity or adipokine measures explained a significant proportion of the variance in telomere length. Vigorous physical activity was positively associated with telomere length (adjusted R 2 =0.019, p=0.009) and accounted for 1.9% of the total variance only in girls.Conclusion-This study, conducted in a biracial adolescent cohort, demonstrated that: (1) race and sex differences in telomere length have already emerged during adolescence; (2) adiposity and adipokines are not associated with telomere length at this age; and (3) the anti-aging effect of vigorous physical activity may begin in youth especially in girls. KeywordsTelomere length; race; sex; adiposity; adipokines; physical activity; adolescents © 2010 Mosby, Inc. All rights reserved. * Address for correspondence: Haidong Zhu MD PhD, Georgia Prevention Institute, Department of Pediatrics, Medical College of Georgia, Augusta, GA, USA, 1120 15 th Street, HS-1640, Augusta, GA 30912-3715, Phone: (706) 721 5470, hzhu@mail.mcg.edu. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.The authors declare no conflicts of interest. In contrast to the considerable information available in adult literature, the knowledge about LTL in adolescent populations is limited. Therefore, the present study aimed to examine the relations of race, sex, adiposity, adipokines and physical activity to telomere length in a relatively large sample of healthy white and black adolescents. NIH Public Access MethodsHealthy adolescents aged 14-18 years including 348 whites and 319 blacks (324 boys) were previously recruited from local public high schools. Written informed consent was obtained from these 18 year olds. For 14-17 year olds, parental consent and subject assent were obtained. Race was determined by self-report of each subject, and by a parent if subject was under 18 years of age. The adolescents were apparently healthy, had no contraindications to any of the study procedures and were taking no medication t...

Paternal age at birth is associated with offspring leukocyte telomere length in the nurses' health study

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Leukocyte Telomere Length and All-Cause, Cardiovascular Disease, and Cancer Mortality: Results From Individual-Participant-Data Meta-Analysis of 2 Large Prospective Cohort Studies

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