Effect of high concentrations of glucose on differentiation of rat trophoblast cells in vitro.
OBJECTIVE
Previous studies have shown that diabetic placentas are characterized by structural and biochemical anomalies, including defects in the differentiation of trophoblasts. In this study, the Rcho-1 cell line was used to investigate the impact of high glucose concentrations on different markers of differentiation of rat trophoblast cells in giant cells (endoreduplication, invasive phenotype and endocrine phenotype).


METHODS
Rcho-1 cells were incubated for 12 days in medium supplemented with different concentrations of glucose and 10% horse serum to optimize differentiation. The cells were examined for the proportion of nuclei showing signs of apoptosis. The effect of high glucose was investigated on the endoreduplication process, on invasive phenotype (secretion of gelatinase B) and on endocrine phenotype (expression of placental lactogen I (PL-I) and II (PL-II) and progesterone secretion).


RESULTS
Apoptosis was not induced by high glucose in Rcho-1. The number of cells was higher in the cultures exposed to high glucose (p<0.05) and their nuclei contained more DNA compared with control cells (p<0.001), while their nuclear size was smaller (p<0.001). Gelatinase B secretion increased during differentiation but no difference was found when gelatinase B secretion from trophoblasts exposed to high glucose was compared with the control cells. Rcho-1 cell cultures showed an increase in PL-I and PL-II mRNA expressions during differentiation and which was not affected by high glucose. Progesterone secretion increased during differentiation in control cultures. However, this increase was abolished when trophoblasts were cultured in high glucose.


CONCLUSIONS
Our data suggest that high glucose influences the endoreduplication process and the steroidogenesis during differentiation of rattrophoblasts.
Hinck
L
L
Physiology of Human Reproduction Research Unit, Catholic University of Louvain Medical School, Avenue Hippocrate 54, 1200 Brussels, Belgium.
Thissen
J P
JP
Pampfer
S
S
De Hertogh
R
R
D000818:Animals; D017209:Apoptosis; D002452:Cell Count; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D002467:Cell Nucleus / Q000187:drug effects / Q000648:ultrastructure; D004305:Dose-Response Relationship, Drug; D005947:Glucose / Q000008:administration & dosage*; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D008940:Mitotic Index; D009994:Osmolar Concentration; D010928:Placental Lactogen / Q000378:metabolism; D011374:Progesterone / Q000378:metabolism; D051381:Rats; D014327:Trophoblasts / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism / Q000502:physiology
C062303:placental lactogen II; C085699:placental lactogen I, rat; D011374:Progesterone; D010928:Placental Lactogen; D020780:Matrix Metalloproteinase 9; D005947:Glucose