Related Experiment Video
Updated: Jun 8, 2026
The 4-vessel Sampling Approach to Integrative Studies of Human Placental Physiology In Vivo
Published on: August 2, 2017
Acid-labile subunit (ALS) gene expression and protein content in human placentas: differences according to birth
Germán Iñiguez1, Felipe Argandoña, Pablo Medina
1Institute of Maternal and Child Research, Faculty of Medicine, University of Chile, Santiago, Chile. giniguez@med.uchile.cl
Context:
In humans, IGF-I and -II have an important role in pre- and postnatal growth. The IGFs circulate in plasma principally as a ternary complex with the IGF binding protein-3 and an acid-labile subunit (ALS), which increases their half life.
Objectives:
The objectives of the study were to determine whether the human placenta expresses the mRNA and protein for ALS and to evaluate any possible differences in the mRNA and protein for ALS in placentas from small (SGA) and appropriate (AGA) or gestational age newborns.
Subjects/Methods:
We studied the placentas from 47 AGA and 42 SGA pregnancies. IGF-I, IGF-II, IGF binding protein-3, and ALS placental mRNA and protein contents were determined in both the basal and the chorionic plates of the placenta.
Results:
We observed that the human placenta expresses the gene and protein for ALS. The ALS mRNA in SGA was higher compared with AGA placentas (0.15 ± 0.01 vs. 0.12 ± 0.01 arbitrary units, respectively, P < 0.05). In addition, the ALS protein content in SGA (31.7 ± 3.3 pmol/g) was higher compared with AGA (22.1 ± 2.3 pmol/g, P < 0.05) placentas.
Conclusion:
We describe that the human placenta expresses the mRNA and the protein for ALS, and we observed an increase in ALS mRNA expression and protein content in SGA compared with AGA placentas.
