Influence of Antenatal Glucocorticosteroid Exposure on Osteoprotegerin and Receptor Activator of Nuclear Factor x03BA;B Ligand Levels in Newborn Infants

Osteoprotegerin and RANKL serum concentrations in neonates of mothers with early-onset pre-eclampsia: comparison with neonates of normotensive mothers

BACKGROUND

Pre-eclampsia is a known risk factor for long-term cardiovascular complications. Osteoprotegerin (OPG) and the receptor activator of nuclear factor κB ligand (RANKL) have been implicated in the pathogenesis of cardiovascular disease. The OPG-RANKL axis function is also altered in pregnant women with pre-eclampsia, but there is lack of data regarding OPG and RANKL concentrations in their neonates.

AIMS

To examine the effects of early-onset pre-eclampsia on OPG and RANKL serum concentrations at birth, taking into account the influence of various perinatal factors.

STUDY DESIGN

OPG and RANKL serum concentrations were measured in 28 premature newborns of mothers with early onset pre-eclampsia, and in 28 preterm and 28 full-term neonates of normotensive mothers (control groups).

RESULTS

Neonates of pre-eclamptic mothers had higher OPG and lower RANKL levels compared to both control groups (Kruskal-Wallis P < 0.0001 and P = 0.014, respectively). Regression analysis showed that pre-eclampsia (P < 0.0001), birth weight z-score (P = 0.048) and antenatal steroid administration (P = 0.034) were significant determinants of OPG levels. Multivariable regression analysis also showed that pre-eclampsia was an independent predictor of increased diastolic and mean blood pressure in these neonates.

CONCLUSIONS

Early-onset pre-eclampsia affects OPG concentrations at birth and is an independent predictor of increased blood pressure in the offspring. Our findings suggest that altered OPG-RANKL axis function may be one of the mechanisms of cardiovascular 'programming' in fetuses exposed to pre-eclampsia.

Early Postnatal Changes of Bone Turnover Biomarkers in Very Low-Birth-Weight Neonates-The Effect of Two Parenteral Lipid Emulsions with Different Polyunsaturated Fatty Acid Content: A Randomized Double-Blind Study

BACKGROUND

ω-3 polyunsaturated fatty acids (n-3 PUFAs) are reported to have beneficial effect on bone mineral density. This study aimed to evaluate early changes of bone turnover biomarkers in very low-birth-weight (VLBW) neonates and the effect of 2 parenteral lipid emulsions (PLEs) with different PUFA composition.

METHODS

This is a randomized double-blind study with parallel design. VLBW neonates (n = 66) receiving parenteral nutrition (PN)>70% of daily energy requirements for >14 days were assigned into 2 groups that were prescribed soybean oil-based (n = 35) and n-3-enriched PLE (n = 31), respectively. Osteoprotegerin (OPG), soluble receptor activator of nuclear factor-kB ligand (sRANKL), osteocalcin (OC), interleukin-6 (enzyme-linked immunoblot assay kits), Ca, and P plasma levels were assessed before PLE implementation (T1) and on day 20 of life (T2).

RESULTS

In the total population, sRANKL and OC significantly increased, whereas OPG and the OPG/sRANKL ratio decreased from T1 to T2. Within each group, T1-to-T2 changes of OC were significant in both groups, whereas those of OPG/sRANKL were significant only in the soybean-based group. Multiple regressions showed an independent effect of group allocation on OPG change. Significant associations were observed between PN duration and sRANKL change (negatively), n-6/n-3 and OC changes (positively), and OPG and sRANKL changes (positively).

CONCLUSIONS

A high bone-turnover rate in VLBW neonates with predominance of bone resorption is confirmed. The lower rate of OPG/sRANKL reduction in the n-3-enriched PLE group indicates that n-3 PUFA-enriched PLEs may help to attenuate early bone loss in VLBW neonates.