Transthyretin as a novel candidate biomarker for preeclampsia

Abstract

Preeclampsia (PE) is considered to be a potentially fatal complication during pregnancy. However, no effective laboratory assessment has been developed to enable early diagnosis and monitoring of PE. The present study aimed to identify differentially expressed transthyretin (TTR) during severe PE and evaluate TTR as a possible biomarker of this disease. TTR levels were determined in the different gestational weeks of normal pregnancy (before 20 weeks, n=41; after 20 weeks, n=39) using enzyme-linked immunosorbent assay (ELISA). TTR concentrations in pregnant females with severe PE (n=43) were compared with those in healthy matched control subjects (n=37) using western blot analysis and ELISA. The median TTR concentration during severe PE in each month of gestation was significantly lower than the concentrations recorded during normal pregnancy. TTR levels in females with severe PE were significantly downregulated compared with the control subjects (P<0.001; area under the curve, 0.834–0.967). Thus, TTR may be used as a potential biomarker of PE.

Serum markers of pre‐eclampsia identified on proteomics

“…Its main function is the transport of thyroxin (T 4 ) and vitamin A (retinol) associated with RBP . In a previous study, TTR in women with severe PE was significantly downregulated compared with the control subjects …”

Preeclampsia is associated with low placental transthyretin levels

“…Elevated levels of TTR have been reported in the amniotic fluid of fetuses with abnormal karyotypes, including trisomy 21 and trisomy 18 [8]. In serum, TTR levels decrease after 12 weeks of gestation [9], similar to the changing demands of TH of fetus. In the placenta, TTR seems to be constant after 13 weeks of gestation [10]; however, the increased expression of TTR in the matrix and vessels within the placenta after 13 weeks suggests that expression in the syncytiotrophoblast (where the TTR transporter regulates TH uptake) should be reduced then.…”

Towards biomarker-based tests that can facilitate decisions about prevention and management of preeclampsia in low-resource settings

“…Three new blood biomarkers [glycosylated fibronectin (GlyFN) [57], transthyretin [58] and vasopressin [59]], and two new urine biomarkers (urine congophilia [60] and urinary adipsin [61]) were identified, which added to our preexisting list of experimental biomarkers (Figure 1). A total of 11 promising single experimental blood and seven urine biomarkers together with the four established markers were ranked according to the following criteria: 1) characteristics related to performance; and 2) other characteristics such as whether a kit or commercial antibodies exist (Table 2A and 2B).…”