Impact of nutritional rehabilitation on the leptin axis in undernourished infants

ABSTRACT

Leptin regulates adipose tissue mass through hypothalamic effects on satiety and energy expenditure. Although it correlates with the fat mass, the circulating concentrations of leptin arc altered by extremes in energy intake such as fasting and overfeeding. Elucidate the effect of intensive nutritional support on the leptin axis in 30 severely undernourished marasmic infants. The study group consisted of 30 infants with third degree marasms of ages 6 to 24 months, mean +/- standard deviation [X +/- SD 13 +/- 7 months]. Control group included 15 age-matched healthy nourished infants. Patients received infant milk-based formula for one month via continuous enteral tube feeding. Serum levels of leptin, soluble leptin receptor [sOB-R], insulin like growth factor-I [IGF-I] and IGF- binding protein-3 [IGFBP-3], as well as anthropometric measurements were determined at the beginning of the study and after one month of refeeding. The following were changes in the undernourished children after the nutritional support leptin and IGFBP-3 increased significantly [P< 0.001], sOB-R decreased significantly [P< 0.001]. Meanwhile, nonsignificant change of IGF-I was noted. Before refeeding, there were significant positive correlation of serum leptin with the indicators of fat accumulation [body mass index [BMI], mid arm circumference [MAC] and IGFBP-3] and negative correlation with the molar excess sOb-R over leptin. After one month of nutritional support, the correlations of serum leptin with the previously mentioned indicators were less closed. Meanwhile, serum leptin is still negatively correlated with the molar excess of sOB-R and positively correlated with serum IGFBP-3. Leptin and the molar excess of sOB-R over leptin are better biomrarkers of nutritional status than IGF-I in undernourished infants during nutritional recovery