Leukocyte telomere length in healthy Caucasian and African-American adolescents: relationships with race, sex, adiposity, adipokines, and physical activity.
OBJECTIVE
To examine the relationships of race, sex, adiposity, adipokines, and physical activity to telomere length in adolescents.


METHODS
Leukocyte telomere length (T/S ratio) was assessed cross-sectionally in 667 adolescents (aged 14-18 years; 48% African-Americans; 51% girls) using a quantitative polymerase chain reaction method. Generalized estimating equations analyses were performed.


RESULTS
Telomere length was greater in the African-American adolescents than in the Caucasian adolescents (age- and sex-adjusted T/S ratio ± SE, 1.32 ± 0.01 vs 1.27 ± 0.01: P = .014) and greater in girls than in boys (age- and race-adjusted T/S ratio ± SE, 1.31 ± 0.01 vs 1.27 ± 0.01; P = .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 = .009) and accounted for 1.9% of the total variance only in girls.


CONCLUSIONS
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 antiaging effect of vigorous physical activity may begin in youth, especially in girls.
Zhu
Haidong
H
Department of Pediatrics, Georgia Prevention Institute, Medical College of Georgia, Augusta, GA 30912-3715, USA. hzhu@mail.mcg.edu
Wang
Xiaoling
X
Gutin
Bernard
B
Davis
Catherine L
CL
Keeton
Daniel
D
Thomas
Jeffrey
J
Stallmann-Jorgensen
Inger
I
Mooken
Grace
G
Bundy
Vanessa
V
Snieder
Harold
H
van der Harst
Pim
P
Dong
Yanbin
Y
D054392:Adipokines / Q000097:blood*; D050154:Adiposity / Q000208:ethnology* / Q000235:genetics*; D000293:Adolescent; D001741:Black or African American / Q000235:genetics; D000886:Anthropometry; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D020022:Genetic Predisposition to Disease / Q000453:epidemiology; D006304:Health Status; D006801:Humans; D007962:Leukocytes; D009043:Motor Activity / Q000502:physiology*; D009765:Obesity / Q000208:ethnology / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000379:methods; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012737:Sex Factors; D016615:Telomere / Q000235:genetics*; D044465:White People / Q000235:genetics
D054392:Adipokines