Effects of uteroplacental insufficiency on growth-restricted rats with altered lung development: A metabolomic analysis

Uteroplacental insufficiency decreases leptin expression and impairs lung development in growth-restricted newborn rats

BACKGROUND

The study aimed to analyze the effect of uteroplacental insufficiency (UPI) on leptin expression and lung development of intrauterine growth restriction (IUGR) rats.

METHODS

On day 17 of pregnancy, time-dated Sprague-Dawley rats were randomly divided into either an IUGR group or a control group. Uteroplacental insufficiency surgery (IUGR) and sham surgery (control) were conducted. Offspring rats were spontaneously delivered on day 22 of pregnancy. On postnatal days 0 and 7, rats' pups were selected at random from the control and IUGR groups. Blood was withdrawn from the heart to determine leptin levels. The right lung was obtained for leptin and leptin receptor levels, immunohistochemistry, proliferating cell nuclear antigen (PCNA), western blot, and metabolomic analyses.

RESULTS

UPI-induced IUGR decreased leptin expression and impaired lung development, causing decreased surface area and volume in offspring. This results in lower body weight, decreased serum leptin levels, lung leptin and leptin receptor levels, alveolar space, PCNA, and increased alveolar wall volume fraction in IUGR offspring rats. The IUGR group found significant relationships between serum leptin, radial alveolar count, von Willebrand Factor, and metabolites.

CONCLUSION

Leptin may contribute to UPI-induced lung development during the postnatal period, suggesting supplementation as a potential treatment.

IMPACT

The neonatal rats with intrauterine growth restriction (IUGR) caused by uteroplacental insufficiency (UPI) showed decreased leptin expression and impaired lung development. UPI-induced IUGR significantly decreased surface area and volume in lung offspring. This is a novel study that investigates leptin expression and lung development in neonatal rats with IUGR caused by UPI. If our findings translate to IUGR infants, leptin may contribute to UPI-induced lung development during the postnatal period, suggesting supplementation as a potential treatment.

Leptin deficiency, a potential mechanism for impaired fetal lung development in uteroplacental insufficiency?

Uteroplacental insufficiency (UPI) is a major cause of fetal growth restriction (FGR). Leptin, an adipokine, has been shown to play a vital role in fetal organogenesis. There is evidence reporting leptin deficiency in preterm and growth-restricted fetuses. In this issue of Pediatric Research, Yuliana et al. report leptin expression and lung development in UPI-induced FGR rats. UPI-induced FGR rats expressed decreased lung leptin and had impaired lung development, as shown by decreased surface area and lung volume. They also found a significant association between lung radial alveolar count, serum leptin, von Willebrand factor, and specific metabolites on metabolomic analyses. Previous studies on leptin supplementation in vivo have been associated with improvement in lung maturation; supporting the evidence, that leptin improves lung growth and development in FGR and may have future therapeutic potential in the improvement of respiratory outcomes in these infants. Future studies to support evidence of this association in humans are warranted.