Department of Paediatric Propedeutics, Medical University of Lublin, ul. A. Gebali 9, 20-091, Lublin, Poland.
Department of Paediatric Endocrinology and Diabetology, Medical University of Lublin, Lublin, Poland.
Ital J Pediatr. 2019 Nov 9;45(1):141. doi: 10.1186/s13052-019-0743-6.
Birth weight and leptin seem to be the factors responsible for early programming of body weight in later life. A marker for leptin action is free leptin index (FLI), which depends on soluble leptin receptor (Ob-Re) (FLI = leptin/Ob-Re). In the present article, we suggest that FLI is modulated partly by cortisol variations observed in newborns in the first days of life and is connected with their postnatal weight loss.
The study group consisted of 44 full-term newborns. Leptin, cortisol and Ob-Re concentrations were determined in the umbilical cord blood (UCB) and in the newborns' blood (NB) on the fourth day of life, free leptin index (FLI = leptin/Ob-Re) was calculated. Correlations between the assessed parameters and the somatic features of the newborns were examined.
Birth weight, length and chest circumference of newborns were positively correlated with leptin concentration in the UCB but not with FLI in the UCB. Cortisol and leptin concentrations, as well as FLI values declined concomitantly with body weight, and were lower on the fourth day of life than on the first one; however, Ob-Re concentration increased (p < 0.0001). There was a positive correlation between the newborns' birth weight loss percentage evaluated on the fourth day of life and FLI in newborns (R = 0.39; p < 0.01). Positive correlations between cortisol and Ob-Re in UCB (R = 0.35; p < 0.02) and in NB (R = 0.36; p < 0.01), as well as a negative correlation between cortisol and FLI (R = -0.32; p < 0.03) in NB were noted.
Our data suggest a possible relationship between cortisol and a soluble leptin receptor (Ob-Re), which changes free leptin index (FLI) and is connected with birth weight loss in newborns. Whether these observations are important for programming of future body weight of children requires further research.
出生体重和瘦素似乎是导致生命后期体重早期编程的因素。瘦素作用的标志物是游离瘦素指数（FLI），它取决于可溶性瘦素受体（Ob-Re）（FLI=瘦素/Ob-Re）。在本文中，我们提出 FLI 部分受新生儿生命头几天观察到的皮质醇变化的调节，并与他们的产后体重减轻有关。
研究组包括 44 名足月新生儿。在脐血（UCB）和新生儿第 4 天的血液（NB）中测定瘦素、皮质醇和 Ob-Re 浓度，计算游离瘦素指数（FLI=瘦素/Ob-Re）。检查评估参数与新生儿体貌特征之间的相关性。
新生儿的出生体重、长度和胸围与 UCB 中的瘦素浓度呈正相关，但与 UCB 中的 FLI 无关。皮质醇和瘦素浓度以及 FLI 值与体重下降呈同步下降趋势，第 4 天低于第 1 天；然而，Ob-Re 浓度增加（p<0.0001）。第 4 天新生儿体重减轻百分比与新生儿 FLI 呈正相关（R=0.39；p<0.01）。UCB 中皮质醇与 Ob-Re 呈正相关（R=0.35；p<0.02）和 NB 中皮质醇与 Ob-Re 呈正相关（R=0.36；p<0.01），以及 NB 中皮质醇与 FLI 呈负相关（R=-0.32；p<0.03）。
我们的数据表明，皮质醇与可溶性瘦素受体（Ob-Re）之间可能存在关系，这种关系改变了游离瘦素指数（FLI），并与新生儿的体重减轻有关。这些观察结果对儿童未来体重编程是否重要需要进一步研究。
