Adiponectin in Human Cord Blood: Relation to Fetal Birth Weight and Gender

Abstract

Adiponectin is an adipocyte-derived plasma protein with insulin-sensitizing and antiatherosclerotic properties. The aim of this study was to examine whether adiponectin is present in human fetal blood, to define its association with fetal birth weight, and to evaluate whether dynamic changes in adiponectin levels occur during the early neonatal period. Cord blood adiponectin levels were extremely high (71.0 +/- 21.0 microg/ml; n = 51) compared with serum levels in children and adults and positively correlated with fetal birth weights (r = 0.4; P < 0.01). No significant differences in adiponectin levels were found between female and male neonates. In addition, there was no correlation between cord adiponectin levels and maternal body mass index, cord leptin, or insulin levels. Cord adiponectin levels were significantly higher compared with maternal levels at birth (61.1 +/- 19.0 vs. 17.6 +/- 4.9 microg/ml; P < 0.001; n = 17), and no correlation was found between cord and maternal adiponectin levels. There were no significant differences between adiponectin levels at birth and 4 d postpartum (61.1 +/- 19.0 vs. 63.8 +/- 22.0 microg/ml; n = 17). These findings indicate that adiponectin in cord blood is derived from fetal and not from placental or maternal tissues. The high adiponectin levels in newborns compared with adults may be due to lack of negative feedback on adiponectin production resulting from lack of adipocyte hypertrophy, low percentage of body fat, or a different distribution of fat depots in the newborns.

Fetal Adiponectin and Resistin in Correlation with Birth Weight Difference in Monozygotic Twins with Discordant Growth

“…This was in contrast to others, i.e. Sivan et al[ 17] and Kajantie et al [28], who analysed cord blood adiponectin in a large cohort of term newborns and found that it was correlated with neonatal BW. Although we could demonstrate an increase in adiponectin with advancing gestational age we found an independent positive association with BW.…”

“…The lack of such negative feedback could contribute to the high adiponectin level in newborns. In addition it has been hypothesized that some particular features of the adipose tissue in newborns, including the presence of brown adipose tissue, might be responsible for the high levels of adiponectin in the fetal circulation [17]. …”

“…This reduction in adiponectin appears to precede the disorder [12], and low levels have been shown to predict the development of the metabolic syndrome. Adiponectin can be detected in cord blood [13,14,15] and might explain the link between SGA and the development of metabolic syndrome in adulthood [16,17,18]. …”

High-Molecular-Weight Adiponectin and Leptin Levels in Cord Blood Are Associated with Anthropometric Measurements at Birth

“…High concentrations of circulating adiponectin have positive health effects such as reduction in proinflammatory cytokines [7], improvement in insulin sensitivity [8], and an increase in fatty acid metabolism [9]. Recently, several investigators reported much higher plasma adiponectin concentrations in cord blood than in the infants’ mothers [10,11,12,13] or in nonobese adults aged 23–50 years [14]. Adiponectin in cord blood is not derived from maternal or placental tissues [12] and does not seem to be related to maternal concentrations [13, 15].…”

“…Recently, several investigators reported much higher plasma adiponectin concentrations in cord blood than in the infants’ mothers [10,11,12,13] or in nonobese adults aged 23–50 years [14]. Adiponectin in cord blood is not derived from maternal or placental tissues [12] and does not seem to be related to maternal concentrations [13, 15]. Some of these reports [12,13,14,15] and others [16, 17] showed a positive relationship between plasma adiponectin concentrations and birth weight; however, such relationships were not found in other studies [10, 11].…”