Leptin, Insulin-like Growth Factor - ¢ñ And Fetal Birth Weight In The Relationship Between

Objective The purpose of this study was to analysis the relationships between leptin, IGF-Ⅰin maternal blood and cord blood, leptin-mRNA in placenta and fetal birth weight, and to explore the effects of leptin and IGF-Ⅰon fetal growth and development. Methods We collected maternal blood before the onset of delivery from 90 healthy cesarean full-term deliveries and cord venous blood immediatedly after birth. All subjects were categorized as SGA(17 cases), AGA(47 cases) and LGA(26 cases) according to birth weight. Leptin and IGF-Ⅰconcentrations were measured by RIA, we analysised the relationships between leptin and IGF-Ⅰ, respectively , with pregnant correlated factors such as birth weight(BW), placental weight, maternal BMI, fetal gender and so on. Furthermore, the correlation between leptin and IGF-Ⅰwas discussed. We collected placental villous tissue on maternal side in 21 healthy full-term pregnant women and divided into three groups: SGA(7 cases), AGA(7 cases) and LGA(7 cases). At the same time, ventral fat tissues were also gathered to be positive control. Total RNA was isolated by using Trizol reagent. We determinated the relative expression of leptin-mRNA in placenta by semi-quantitative nested-RT-PCR and analysised its relationships with pregnant related factors such as leptin in maternal blood and cord blood, placental weight and fetal birth weight. Results (1) Maternal leptin was very significantly higher than cord leptin(8.81±3.02 μg/l vs 5.05±2.20 μg/l; P ﹤0.001) and very markedly positively correlated with maternal BMI(P﹤0.001), but not with birth weight, Ponderal index and placental weigh(tP﹥0.05). Among three groups, there were no significant difference(P﹥0.05). (2) The levels of IGF-Ⅰin maternal blood and cord blood were 308.99±105.02 μg/l versus 151.96±117.18 μg/l and extremely significant difference existed (P﹤0.001). Maternal IGF-Ⅰwas not correlated with birth weight and Ponderal index(P﹥0.05); but correlated with placental weight(P﹤0.01). Among three groups, there were no sinificant difference(P﹥0.05). (3) Cord leptin was 5.05±2.20 μg/l,and was very markedly correlated positively with birth weight , Ponderal index, the expression of leptin-mRNA in placenta and placental weight(P﹤0.001). Among three groups, there were very significant difference(P﹤0.001), in LGA group and in SGA group cord leptin was, respectively, very higher and lower than that in AGA group. (4) Cord IGF-Ⅰin LGA infants was higher than that in AGA; in SGA that was lower than that in AGA infants.Birth weight, Ponderal index and placental weight were significantly positively correlated with cord IGF-Ⅰ( P﹤0.05). (5) The expression of leptin-mRNA in AGA placenta was lower and higher, respectively, than that in LGA placenta and in SGA placenta(P﹤0.05). The relative level of leptin-mRNA in placenta was positively associated to placental weight, birth weight and Ponderal index(P﹤0.001), but was not different with fat tissues(P﹥0.05). (6) Very significantly positive correlation existed between placental weight and birth weight or Ponderal index (P﹤0.001). (7) There was no relation between any two among maternal leptin, maternal IGF-Ⅰ, cord leptin and cord IGF-Ⅰ( P>0.05). Conclusion (1) Maternal leptin and maternal IGF-Ⅰare not correlated to fetal birth weight. So to monitor maternal leptin and maternal IGF-Ⅰcan not predict fetal birth weight during pregnancy. (2) Maternal IGF-Ⅰi s positively related to placental weight, indirectly take part in fetal growth and development by regulating placental function.Maternal IGF-Ⅰreflects placental function in certain extent, so administering IGF-Ⅰin maternal blood may improve placental function, and providing new theory for curing FGR in clinic. (3) Cord leptin and cord IGF-Ⅰindepently regulate fetal growth and development in utero, respectively, by various patterns. In theory, we can predictfetal birth weight and fetal development status by monitoring cord leptin and cord IGF-Ⅰduring pregnancy. (4) The expression of leptin-mRNA in...