Leptin And Fetal Growth And Development Study Of The Relationship

Objective To investigate whether placental tissues produce leptin and determine the relationship between expression levels of leptin-mRNA in placenta and fetal growth and development. Methods 52 neonates were divided into 3 subgroups: (1) birth weight large for gestational age (LGA)(n=14), (2) birth weight appropriate for gestational age (AGA)(n=21), (3) birth weight small for gestational age (SGA)(n=17). Reverse transcription-polymerase chain reaction (RT-PCR) technique was used to detect human leptin-mRNA derived from placental-RNA. The expression levels of leptin-mRNA were quantitated using fluorescence intensity analysis. The correlations of expression level of placental leptin-mRNA with placental weight, birth weight, newborn Ponderal index (PI) , maternal weight, maternal body mass index (BMI) and gender were studied.Results The expression levels of placental leptin-mRNA in LGA infants (119.7±13.0) and SGA infants (76.8±15.1) were significantly higher and lower respectively than that in the AGA infants (94.7±17.4) (P<0.001 and 0.005). The significant positive correlations were observed between the leptin-mRNA expression in placenta and placental weight (r=0.54), birth weight (r=0.59) and Ponderal index (r=0.56 ). There were no correlations between the expression levels of placental leptin-mRNA and maternal weight (r=0.21) and maternal BMI (r=0.18). The difference of placental leptin-mRNA expression between female and male neonates was statistically not significant.Conclusions The placenta is one of the major sources of leptin in the fetal circulation. We suggest that there are strong associations between the expression levels of placental leptin-mRNA and fetal growth. Placental leptin may play an important role in fetal growth as a regulator. Gender differences were not found in placental leptin-mRNA expression.