Biochemical investigation of lipolytic activity in macrosome babies’ placentas

Abstract

Background: The aim of our study was to investigate biochemical properties of triacylglycerol acylhydrolase in the microvillous plasma membrane of macrosomic babies’ placentas. Materials and methods: Fifteen placentas of mothers of macrosomic babies were included in this study and compared to 15 placentas of mothers of normal weight babies. We included singleton pregnancies who delivered between 36 and 41 completed weeks gestation. Macrosomia was confirmed by birth weight > 4 kg. We focused on a triacylglycerol lipase of placental villi which may be involved in the development of fetal macrosomia. Results: A true lipase (EC.3.1.1.3) was isolated from placentas of women with normal fetal weights (the controls), and those of macrosomic babies. Placental microvillus enzyme was active at 37°C and pH 7.4 for both groups. The specific activity of the enzyme was higher in the macrosomic babies’ placentas than those of controls. Enzymatic activity was enhanced in the presence of calcium by a factor of 2.  We also observed the tendency of the enzyme to aggregation when loading the purified extract onto a DEAE-cellulose ion exchange column. Conclusion: The detected enzyme in macrosomic babies’ placentas showed a higher specific activity which could be related to lipid transfer disorder across the placenta in macrosomia.