Dynamic changes of orexin A and leptin in obese children during body weight reduction.
In this study, we describe changes of plasma levels of the hypothalamic neuropeptide orexin A in obese children during the reduction of body weight and its relationship to other biochemical and anthropometrical parameters. We measured orexin A fasting plasma levels by the RIA method in 58 obese children--33 girls and 25 boys; mean age 13.1+/-0.38 years (range 7-18.5) before and after 5 weeks of weight-reduction therapy. Leptin, IGF-1, and IGFBP-3 levels were measured in all the subjects and were compared to orexin A levels and anthropometrical data. Average weight in subjects before weight-reduction was 74.2+/-2.79 kg and after weight-loss 67.4+/-2.60 kg (p<0.0001). Orexin A levels before the therapy were 33.3+/-1.97 pg/ml and after the therapy 51.7+/-3.07 pg/ml (p<0.0001). Levels of orexin A were not significantly different between girls and boys (p=0.7842). We found negative correlation between orexin A and age (r = -0.5395; p<0.0001), body height (r = -0.4751; p=0.0002), body weight (r = -0.4030; p=0.0017) and BMI (r = -0.2607; p=0.0481). No correlation was found between orexin A and IGF-1, IGFBP-3 or leptin. Orexin A plasma levels increased during body weight loss, whereas the reverse was true for leptin levels. These findings support the hypothesis that orexin A may be involved in regulation of nutritional status in children.
Bronský
J
J
Department of Pediatrics, 2nd Medical Faculty, Charles University and University Hospital Motol, Prague, Czech Republic. bronsky@email.cz
Nedvídková
J
J
Zamrazilová
H
H
Pechová
M
M
Chada
M
M
Kotaska
K
K
Nevoral
J
J
Průša
R
R
D000293:Adolescent; D000375:Aging / Q000378:metabolism; D001827:Body Height / Q000502:physiology; D015992:Body Mass Index; D001835:Body Weight / Q000502:physiology; D002648:Child; D005260:Female; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins / Q000097:blood*; D020738:Leptin / Q000097:blood*; D008297:Male; D009479:Neuropeptides / Q000097:blood*; D009752:Nutritional Status; D009765:Obesity / Q000097:blood*; D000068797:Orexins; D011863:Radioimmunoassay; D015431:Weight Loss / Q000502:physiology*
C000596229:HCRT protein, human; D047908:Intracellular Signaling Peptides and Proteins; D020738:Leptin; D009479:Neuropeptides; D000068797:Orexins; D007334:Insulin-Like Growth Factor I