[Blood leptin, orexins and NPY levels and their relations in obese children].
OBJECTIVE
To investigate the concentration levels of leptin, orexins and neuropeptide Y (NPY) in the blood of obese children, and to analysed the relationship between these substances.


METHODS
RIA methods were used to measure the concentrations of leptin, orexinA, orexinB, and NPY in the blood of 98 obese children [BMI: male (29.24 +/- 1.87) kg/mZ, female (28.12 +/- 2.30) kg/m2] and in 104 normal children [BMI: male (20.49 +/- 1.95) kg/m2, female (19.59 +/- 1.51) kg/m2] as the control group.


RESULTS
The leptin concentrations in obese children [male (26.00 +/- 14.66) ng/mL; female (33.59 +/- 14.63) ng/mL] were higher than those in the control group [male (6.65 +/- 44.49) ng/mL; female [10.48 +/- 5.52) ng/mL P < 0.013]. The concentrations of plasma orexinA in obes children [male (3.23 +/- 1.86) pg/mL; female (3.38 +/- 1.80) pg/mL] were lower than those in the control group [male (4.52 +/- 1.52) pg/mL; female (4.71 +/- 1.53) pg/mL P < 0.05]; Negative correlations between leptin and NPY were noted in the obesity group (r = -0.302) and the control group (r = -0.310, P < 0.01), while the slopes in the two groups were different (control group -2.969; obese group -0.809). A positive correlation between NPY and orexinA was noted (r = 0.207, P < 0.05). The fluctuation range of orexinA in obese children was markedly narrowed when compared with that in the control group.


CONCLUSIONS
The concentration level of peripheral orexinA and leptin in the obese and non-obese children change inversely. The obesity in children correlates with the concentrations of orexinA, leptin, NPY as well as with their interactions.
Lou
Xiao-min
XM
Department of Envirommental Health, West China School of Public Health, Sichan University, Chengdu 610041, China.
Duan
Guang-cai
GC
Chen
Jiang
J
Zhou
Yan
Y
Hu
Qiao-yun
QY
Heng
Zheng-chang
ZC
D000293:Adolescent; D002648:Child; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000097:blood*; D020738:Leptin / Q000097:blood*; D009478:Neuropeptide Y / Q000097:blood*; D009479:Neuropeptides / Q000097:blood*; D009765:Obesity / Q000097:blood*; D000068797:Orexins
C000596229:HCRT protein, human; D047908:Intracellular Signaling Peptides and Proteins; D020738:Leptin; D009478:Neuropeptide Y; D009479:Neuropeptides; D000068797:Orexins