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Updated: May 29, 2026
06:33
Genetic Analysis of Hereditary Transthyretin Ala97Ser Related Amyloidosis
Published on: June 9, 2018
Ontogenic changes in placental transthyretin
1School of Medicine, The University of Queensland, Herston 4006, Brisbane, Australia.
Placenta
|September 28, 2011
Summary
Placental transthyretin (TTR) is present from early pregnancy, with levels increasing significantly during the first trimester. This suggests TTR may aid in transporting maternal thyroid hormone to the developing fetus.
Area of Science:
- Reproductive Biology
- Endocrinology
- Developmental Biology
Background:
- Maternal thyroid hormone (TH) is crucial for fetal development before fetal TH secretion begins around 16 weeks gestation.
- The mechanisms of transplacental TH delivery are not fully understood.
- Transthyretin (TTR), a TH-binding protein, is produced by the placenta and may play a role in TH transport.
Purpose of the Study:
- To investigate the ontogeny of placental transthyretin (TTR) expression during early and late pregnancy.
- To determine changes in placental TTR mRNA and protein levels throughout gestation.
Main Methods:
- Placentas were collected from pregnancies between 6-17 weeks gestation (n=44) and term pregnancies (n=5).
- Real-time PCR, western blotting, and immunohistochemistry were employed to quantify TTR mRNA and protein levels.
Main Results:
- Significant positive correlations were found between gestational age and placental TTR mRNA (r=0.974) and protein (r=0.901) levels from 6 to 13 weeks gestation.
- TTR expression levels plateaued between 13-17 weeks gestation and remained similar at term.
- Strong correlation (r=0.916) was observed between TTR mRNA and protein levels in individual placental samples.
Conclusions:
- Transthyretin (TTR) is expressed in the human placenta starting from at least 6 weeks gestation.
- Placental TTR levels increase during the first trimester, coinciding with rising placental oxygen tensions.
- It is hypothesized that placental TTR facilitates the transplacental transfer of thyroid hormone to the fetus.
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