Identification of caspase-6 in rat blastocysts and its implication in the induction of apoptosis by high glucose
Previous investigations have shown that maternal diabetes impairs rodent embryo development during the earliest phase of gestation. Exposure to high concentrations of glucose before implantation results in a decrease in the number of cells per embryo and in a concomitant increase in two nuclear mark...
Saved in:
Published in | Biology of reproduction Vol. 68; no. 5; pp. 1808 - 1812 |
---|---|
Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
Madison, WI
Society for the Study of Reproduction
01.05.2003
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | Previous investigations have shown that maternal diabetes impairs rodent embryo development during the earliest phase of gestation.
Exposure to high concentrations of glucose before implantation results in a decrease in the number of cells per embryo and
in a concomitant increase in two nuclear markers of apoptosis: chromatin degradation and nuclear fragmentation. In the present
study, we show that caspase-6 is expressed in rat blastocysts, using reverse transcription-polymerase chain reaction (RT-PCR)
and immunocytochemistry. Caspase-6 is detected in all cells of the blastocyst and is excluded from the nucleus. To assess
the role of caspase-6 in the glucose-induced apoptosis, rat blastocysts were incubated for 24 h in either 6 or 28 mM glucose
in the presence or absence of a specific inhibitor of caspase-6 (VEID-CHO, 100 nM). After incubation, blastocysts were examined
for the proportion of nuclei showing signs of chromatin degradation and nuclear fragmentation. Addition of VEID-CHO was found
to inhibit nuclear fragmentation, but did not prevent the increase in chromatin degradation triggered by excess glucose. Our
data indicate that chromatin degradation and nuclear fragmentation are two nuclear damages that are induced separately by
high glucose in rat blastocysts. Furthermore, nuclear fragmentation in rat blastocysts is apparently mediated by the activation
of caspase-6. |
---|---|
ISSN: | 0006-3363 1529-7268 |
DOI: | 10.1095/biolreprod.102.010009 |