Associations between serum apelin-12 levels and obesity-related markers in Chinese children.
OBJECTIVE
To investigate possible correlations between apelin-12 levels and obesity in children in China and associations between apelin-12 and obesity-related markers, including lipids, insulin sensitivity and insulin resistance index (HOMA-IR).


METHODS
Forty-eight obese and forty non-obese age- and gender-matched Chinese children were enrolled between June 2008 and June 2009. Mean age was 10.42 ± 2.03 and 10.86±2.23 years in obesity and control groups, respectively. Main outcome measures were apelin-12, BMI, lipids, glucose and insulin. HOMA-IR was calculated for all subjects.


RESULTS
All obesity group subjects had significantly higher total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), insulin levels and HOMA-IR (all P<0.05). In separate analyses, obese girls had significantly higher LDL-C, insulin and HOMA-IR than controls, and obese boys had significantly higher TC, TG, insulin and HOMA-IR than controls (all P<0.05). Apelin-12 levels were significantly higher in obese girls compared to controls (P = 0.024), and correlated positively with TG in all obese subjects. Among obese girls, apelin-12 levels correlated positively with TG, insulin and HOMA-IR after adjusting for age and BMI. In all boys (obese and controls) apelin-12 was positively associated with fasting plasma glucose (FPG). No significant correlations were found in either group between apelin-12 levels and other characteristics after adjusting for age, sex, and BMI.


CONCLUSIONS
Apelin-12 levels are significantly higher in obese vs. non-obese girls in China and correlate significantly with obesity-related markers insulin, HOMA-IR, and TG. Increased apelin-12 levels may be involved in the pathological mechanism of childhood obesity.
Pediatric Department, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China.
Hong-Jun
HJ
Ba
Pediatric Department, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China.
Hong-Shan
HS
Chen
Pediatric Department, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China.
Zhe
Z
Su
Pediatric Department, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China.
Min-Lian
ML
Du
Pediatric Department, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China.
Qiu-Li
QL
Chen
Pediatric Department, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China.
Yan-Hong
YH
Li
Pediatric Department, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China.
Hua-Mei
HM
Ma
D000886:Anthropometry; D044466:Asian People; D015415:Biomarkers / Q000378:metabolism*; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D002648:Child; D005260:Female; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood*; D008055:Lipids / Q000097:blood; D008297:Male; D009765:Obesity / Q000097:blood / Q000175:diagnosis*; D012737:Sex Factors; D018709:Statistics, Nonparametric
D015415:Biomarkers; D001786:Blood Glucose; D036341:Intercellular Signaling Peptides and Proteins; D008055:Lipids; C495200:apelin-12 peptide