Adiponectin, leptin and insulin levels at birth and in early postnatal life in neonates with hypoxic ischemic encephalopathy.

Background: Hypoxic ischemic encephalopathy (HIE) occurs in one to three per 1000 live full-term births. Fifteen to twenty percent will die in the postnatal period, and an additional 25 % will develop severe and permanent neuropsychological sequalae. The control of growth and nutritional status in the fetus and neonate is a complex mechanism, in which also hormones produced by adipose tissue, such as adiponectin and leptin are involved. The aim of this study was to measure the levels of adiponectin, leptin and insulin in neonates with HIE at birth and in early postnatal life and comparing them with normal healthy AGA and SGA neonates.

Methods: This study carried out on 80 full-term neonates born in Minia university hospital during the period from May 2013 to December 2014. They were divided into group I included 25 neonates with HIE and group II included 55 normal healthy neonates (30 appropriate for gestational age (AGA) and 25 small for gestational age (SGA)). Weight, length, head circumference, body mass index (BMI), glucose, adiponectin, leptin and insulin levels were measured for all neonates. Adiponectin, leptin and insulin levels were compared between neonates with HIE and normal healthy neonates as well as between AGA and SGA neonates at birth, 2nd and 6th days of life.

Results: Adiponectin and leptin levels were significantly higher at birth then began to decrease during the first postnatal week in all neonates while insulin level increased during the same period. Serum adiponectin levels were significantly lower while serum leptin and insulin levels were significantly higher in neonates with HIE than healthy neonates. In all neonates, the serum adiponectin level was positively correlated at birth with weight, length, BMI and leptin levels but not with insulin level. In neonates with HIE, serum adiponectin level was not correlated with weight, BMI, leptin level or insulin level. In all neonates, the serum leptin level was positively correlated at birth with body weight, height and BMI. In neonates with HIE serum leptin levels were not correlated with weight, BMI or insulin level after birth. There were no correlations between either leptin or adiponectin serum levels or any of the studied parameters in neonates with HIE.

Conclusions: Neonates who are suffering from HIE had lower serum levels of adiponectin and higher serum levels of leptin and insulin than normal healthy neonates at birth and during the early postnatal period. The decline of leptin and increased the insulin levels after birth in all neonates may be important for the stimulation of feeding behavior and the acquisition of energy homeostasis during the early postnatal life. Positive significant correlations between adiponectin, leptin, body weight and body mass indices were present in normal healthy neonates but not in neonates with HIE reflecting the effect of hypoxia on the regulatory mechanisms controlling the adipose tissue functions.