Leptin Levels of the Perinatal Period Shape Offspring’s Weight Trajectories through the First Year of Age

Abstract

Background: Leptin is a hormone regulating lifetime energy homeostasis and metabolism and its concentration is important starting from prenatal life. We aimed to investigate the association of perinatal leptin concentrations with growth trajectories during the first year of life. Methods: Prospective, longitudinal study, measuring leptin concentration in maternal plasma before delivery, cord blood (CB), and mature breast milk and correlating their impact on neonate’s bodyweight from birth to 1 year of age, in 16 full-term (FT), 16 preterm (PT), and 13 intrauterine growth-restricted (IUGR) neonates. Results: Maternal leptin concentrations were highest in the PT group, followed by IUGR and FT, with no statistical differences among groups (p = 0.213). CB leptin concentrations were significantly higher in FT compared with PT and IUGR neonates (PT vs. FT; IUGR vs. FT: p < 0.001). Maternal milk leptin concentrations were low, with no difference among groups. Maternal leptin and milk concentrations were negatively associated with all the neonates’ weight changes (p = 0.017 and p = 0.006), while the association with CB leptin was not significant (p = 0.051). Considering each subgroup individually, statistical analysis confirmed the previous results in PT and IUGR infants, with the highest value in the PT subgroup. In addition, this group’s results negatively correlated with CB leptin (p = 0.026) and showed the largest % weight increase. Conclusions: Leptin might play a role in neonatal growth trajectories, characterized by an inverse correlation with maternal plasma and milk. PT infants showed the highest correlation with hormone levels, regardless of source, seeming the most affected group by leptin guidance. Low leptin levels appeared to contribute to critical neonates’ ability to recover a correct body weight at 1 year. An eventual non-physiological “catch-up growth” should be monitored, and leptin perinatal levels may be an indicative tool. Further investigations are needed to strengthen the results.

Maternal Blood Adipokines and Their Association with Fetal Growth: A Meta-Analysis of the Current Literature

“…Contradictory to the above data, there are studies that have demonstrated lower maternal serum leptin levels between growth-restricted cases and uncomplicated controls. However, the findings of the current published bibliography alongside the results of our meta-analysis suggest that leptin may indeed have a role in the pathophysiology of several adverse events of the pregnancy, and it has been proposed that the comparison of leptin concentrations against the reference values that have been published [ 36 ] might be a useful prediction asset of such complications [ 14 ]. The studies conclude that both the up- and down-regulation of serum leptin is originating from the deterioration of the placenta, with a number of published data revealing the critical effect of those alterations in preterm newborns without being limited in the antenatal period but also influencing the growth trajectories of the affected neonates [ 14 ].…”

“…The studies published so far have demonstrated both higher [ 9 , 10 , 11 ] and lower [ 12 , 13 ] levels, as well as no association [ 14 , 15 ] between maternal serum leptin levels and fetal growth restriction. Most of the available data suggest that the mean levels of leptin appear to be elevated in growth-restricted fetuses compared to appropriately grown controls, a difference that becomes further aggregated when growth restriction is accompanied by the development of preeclampsia [ 35 ].…”

“… Newcastle–Ottawa scale (NOS) quality assessment of the included studies [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ].√: the criterion under question is met, √√: two adjusting factors were taken into consideration. …”

“… Summary of outcomes according to the adipokine investigated and the study included [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ]. NS: not studied.…”

The Mother–Child Dyad Adipokine Pattern: A Review of Current Knowledge

“…Moreover, the reported relationships among the analyzed parameters, including perinatal risk factors, in mother-infant dyads are also summarized (Table 2). Only seven reports presented data for three different biological materials, namely for maternal plasma, cord plasma, and placenta [113,127,128,143,146,148,156], and two papers analyzed three different biological materials in another layout, namely for maternal plasma, cord plasma and maternal milk, or infant's plasma [119,144]. However, the most frequently studied pair of biological materials in the analyzed set of studies was that of maternal plasma and cord serum (23 out of 47), followed by maternal plasma and breast milk (8 out of 47) (Table 2).…”