Retinol binding protein 4 is associated with adiposity-related co-morbidity risk factors in children.
OBJECTIVE
In adults, elevated levels of retinol binding protein 4 (RBP4) have been associated with biochemical markers of adiposity-related co-morbidities including insulin resistance, dyslipidemia, hypertension, and abdominal obesity. This study examined the relationship between RBP4 and risk factors for co-morbidities of adiposity in a population of ethnically diverse children in early- to mid-adolescence in the public school system of New York City.


METHODS
We analyzed anthropometric (body mass index, % body fat, waist circumference), metabolic (lipids, glucose), and inflammatory (TNF-alpha, interleukin-6, C-reactive protein, adiponectin) markers for adiposity-related co-morbidities and serum alanine aminotransferase (ALT) in 106 school children (65 males, 41 females) 11-15 years of age (mean +/- SD = 13.0 +/- 0.1 years) who were enrolled in the Reduce Obesity and Diabetes (ROAD) project. Insulin sensitivity was assessed by quantitative insulin sensitivity check index. Insulin secretory capacity was measured as acute insulin response and glucose disposal index.


RESULTS
Serum RBP4 was significantly correlated directly with ALT, triglycerides, and triglyceride z-score, and inversely correlated with adiponectin. Correlations with ALT and adiponectin remained significant when corrected for % body fat, age, and gender. There were significant ethnic differences in the relationship of RBP4 to ALT, glucose disposal index and adiponectin.


CONCLUSIONS
In early- to mid-adolescents, circulating concentrations of RBP4 are correlated with multiple risk factors for adiposity-related co-morbidities. The observation that many associations persisted when corrected for % body fat, suggests that RBP4 can be viewed as an independent marker of adiposity-related co-morbidity risk in children.
Division of Pediatrics Endocrinology, Children's Hospita of New York, Presbyterian Hospital-Columbia University Medical Center, New York, NY 10032, USA. rushika.conroy@baystatehealth.org
Rushika
R
Conroy
Yomery
Y
Espinal
Ilene
I
Fennoy
Siham
S
Accacha
Claudia
C
Boucher-Berry
Dennis E
DE
Carey
Sharron
S
Close
Deborah
D
DeSantis
Rishi
R
Gupta
Abeer A
AA
Hassoun
Loretta
L
Iazzetti
Fabean J
FJ
Jacques
Amy M
AM
Jean
Lesly
L
Michel
Katherine
K
Pavlovich
Robert
R
Rapaports
Warren
W
Rosenfeld
Elisabeth
E
Shamoon
Steven
S
Shelov
Phyllis W
PW
Speiser
Svetlana
S
Ten
Michael
M
Rosenbaum
D050154:Adiposity / Q000235:genetics*; D000293:Adolescent; D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition / Q000235:genetics; D002648:Child; D015897:Comorbidity; D005260:Female; D006801:Humans; D007249:Inflammation / Q000453:epidemiology / Q000235:genetics; D007333:Insulin Resistance / Q000235:genetics; D008055:Lipids / Q000097:blood; D008297:Male; D009765:Obesity / Q000453:epidemiology* / Q000235:genetics*; D015995:Prevalence; D054839:Retinol-Binding Proteins, Plasma / Q000235:genetics*; D012307:Risk Factors
D001786:Blood Glucose; D008055:Lipids; C101326:RBP4 protein, human; D054839:Retinol-Binding Proteins, Plasma