Role of the alpha hemoglobin-stabilizing protein in HELLP syndrome, intrauterine growth restriction and fetal death


      The alpha hemoglobin-stabilizing protein (AHSP) is a small protein that binds and stabilizes alpha-hemoglobin, thus inhibiting the production of reactive oxygen species. It was originally identified as a protein downregulated in transmissibile spongiform encephalopaties, and therefore considered a marker of neurodegeneration Our objective was to evaluate the expression of AHSP in placentae from women with HELLP syndrome, intrauterine growth restriction (IUGR), and fetal death.

      Study design

      Placentae were collected immediately after caesarean section from normal term pregnancies (n=10) and pregnancies complicated by HELLP syndrome (n=10), IUGR (n=10), or fetal death (n=6). Placental AHSP mRNA content was determined using real-time quantitative RT-PCR. All values were expressed as mean ± SD of AHSP copy number (adjusted for beta-actin copy number), One way ANOVA was used for statistical analysis (significance: p < 0.05).


      The two groups were comparable for maternal age and parity, but normal patients delivered later in gestation, had a higher birthweight and lower blood pressure than HELLP and IUGR. No difference in blood pressure was observed between women with fetal death and controls. The mRNA expression of AHSP was significantly decreased in placentae obtained from patients with pregnancies complicated by HELLP syndrome (4.16E10-4 ± 1.77) IUGR (7.55E10-4 ± 6.4) or fetal death (4.19E10-4 ± 3.37) compared with controls (28.47E10-4 ± 14.86; p< 0.01).


      AHSP is present in the placenta, and its mRNA expression is downregulated in pregnancy complications that are known to be associated with oxidative stress. AHSP downregulation enhances oxidative damage, and may be involved in the pathogenic mechanisms leading to the adverse pregnancy outcomes.
      Acknowledgements: This work was supported by the Italian Ministry for University and Scientific Research through PRIN 2004-068971-007.