Discovery of the serum biomarker proteins in severe preeclampsia by proteomic analysis

Preeclapsia (PE) is a severe disorder that occurs during pregnancy, leading to maternal and fetal morbidity and mortality. PE affects about 3-8% of all pregnancies. In this study, we conducted liquid chromatographymass spectrometry/mass spectrometry (LC-MS/MS) to analyze serum samples depleted of the six most abundant proteins from normal and PE-affected pregnancies to profile serum proteins. A total of 237 proteins were confidently identified with < 1% false discovery rate from the two groups of duplicate analysis. The expression levels of those identified proteins were compared semiquantitatively by spectral counting. To further validate the candidate proteins with a quantitative mass spectrometric method, selective reaction monitoring (SRM) and enzyme linked immune assay (ELISA) of serum samples collected from pregnant women with severe PE (n = 8) or normal pregnant women (n = 5) was conducted. alpha2-HS-glycoprotein (AHSG), retinol binding protein 4 (RBP4) and alpha-1-microglobulin/bikunin (AMBP) and Insulin like growth factor binding protein, acid labile subunit (IGFBP-ALS) were confirmed to be differentially expressed in PE using SRM (P < 0.05). Among these proteins, AHSG was verified by ELISA and showed a statistically significant increase in PE samples when compared to controls.

Insulin-like growth factors and their binding proteins in children with IDDM.

The structure of insulin-like growth factor (IGF), especially IGF-I, and its receptor is similar to that of insulin. Therefore, the changes of IGFs and IGF-binding proteins may be related to glucose homeostasis in children with insulin dependent diabetes mellitus (IDDM). Sixty-three fasting blood samples of 21 children with IDDM attending 3 consecutive diabetic clinics were studied. The HbA1c progressively decreased from the 1st to the 3rd visit. IGF-I levels, both total and free forms, were not significantly different from that of control. IGFBP-3 levels in 3 visits (3406+/-305, 3376+/-252, and 2406+/-247 ng/mL) were significantly lower than that of control (5020+/-415 ng/mL) with the p value of 0.007, 0.002, and < 0.001 respectively. IGFBP-1 levels in the 1st and 2nd visits (102.1+/-12.9 and 114.1+/-14.5 ng/mL) were significantly higher than that of control (60.1+/-15.2 ng/mL) with the p value of 0.03 and 0.01 respectively, but not in the 3rd visit. IGF-I level had a positive correlation with IGFBP-3 (R=0.56, p=0.01) and free IGF-I (R=0.53, p=0.01). Free IGF-I had a negative correlation with IGFBP-1 (R=-0.64, p=0.01). IGF-II at the 15 visit had a negative correlation with HbA1c (R=-0.49, p=0.047). The authors found no correlations between IGF-I, IGFBP-3, free IGF-I, IGFBP-1 and HbA1c in the study. The patients' height SDS followed the genetic height potential. It was, therefore, postulated that a near normal free IGF-I level in diabetic children resulted from a balance of interaction between IGFBP-1 and IGFBP-3 to total IGF-I in order to keep the normal metabolic status as much as possible.