Context: Leptin might be more important as a starvation hormone than as a satiety signal. The role of the soluble leptin receptor (sOB-R) and its regulation in children with protein energy malnutrition (PEM) is poorly understood.
Design: We elucidated the effect of intensive nutritional support on the leptin axis in 26 severely malnourished toddlers who received infant milk-based formula for 2 wk via continuous enteral tube feeding followed by 2 wk ad libitum feeding. Serum levels of leptin, sOB-R, IGF-I, and IGF-binding protein-3 as well as anthropometric measurements were determined at the beginning of the study and at 2-wk intervals. The control group consisted of 13 well-nourished children.
Results: The following were changes in the PEM toddlers after the nutritional support. Leptin increased significantly (P < 0.001), reaching 166% of levels observed in control group. sOB-R decreased significantly (P < 0.001), and a 142-fold molar excess of sOB-R over leptin was found. There were significant correlations between leptin and IGF-I after 2 wk and IGF-binding protein-3 during the whole study. sOB-R was not correlated with any anthropometric data, whereas IGF-I was a predictor of sOB-R variance in the PEM toddlers (19.9%, P = 0.022).
Conclusion: It can be concluded that sOB-R has a modulatory effect on leptin in PEM children during nutritional recovery and participates in their adaptive survival mechanisms. Leptin and the molar excess of sOB-R over leptin are better biomarkers of nutritional status than IGF-I in PEM children during nutritional recovery.