INVESTIGADORES
JAWERBAUM Alicia Sandra
congresos y reuniones científicas
Título:
Increased metalloproteinases in fetoplacental unit of diabetic rats at midgestation:
Autor/es:
GONZÁLEZ ELIDA, PUSTOVRH MARÍA C., LÓPEZ COSTA JUAN JOSÉ, CAPOBIANCO EVANGELINA, WHITE VERÓNICA, MARTÍNEZ NORA, JAWERBAUM ALICIA
Lugar:
Luso, Portugal
Reunión:
Congreso; 36th Annual Meeting, Diabetes and Pregnancy Study Group (DPSG), EASD.; 2004
Institución organizadora:
Diabetes and Pregnancy Study Group (DPSG), European Association for the Study of Diabetes (EASD).
Resumen:
Matrix metalloproteinases (MMPs) are mayor regulators of extracellular matrix
remodelling during placental and fetal development. Reactive oxygen species (ROS) are
involved in the cleavage of the MMPs proenzymes leading to the formation of enzymes
with biological activity. Hyperglycemia is responsible of an enhanced production of ROS
and of abnormal levels of MMPs in different cell types. In order to determine whether the
diabetic milieu induces alterations in the oxidative state and in MMPs levels and regulation
in the fetoplacental unit during rat midpregnancy, we evaluated a) MMP-2 and MMP-9
activities (zymography) and distribution (inmunohistochemistry) as well as b) lipid
peroxidation and the influence of ROS on MMPs activity in the placenta (maternal and fetal
side) and fetus from controls (C) and neonatal-streptozotocin-induced diabetic (n-STZ) rats
at midgestation. In the placenta of n-STZ diabetic rats a stronger expression of MMPs was
detected (p<0.01) in comparison to controls. Placental MMP-2 and MMP-9 activities from
diabetic animals were higher than those found in the control group (p<0.01). MMP-9
activity was absent both in C and n-STZ fetuses, while fetal MMP-2 activity was higher in
diabetic tissues than in C (p<0.05). Hydrogen peroxide and superoxide dismutase additions
to fetal and decidual explants produced respectively an enhancement (p<0.01) and a
decrease (p<0.05) of MMP-2 and MMP-9 activities, while no changes could be observed in
the fetal side of the placenta. On the other hand, an increased production of lipid peroxides
was detected in the fetal side (p<0.05) and in the fetus (p<0.02) from n-STZ animals
compared to C, while placental TBARs content was equal in the maternal side from control
and diabetic rats. We conclude that placental and fetal MMPs activities are higher in n-STZ
than in C animals, an enhancement that is likely to be influenced by high levels of ROS.
Our results also suggest that the decidua is able to compensate the oxidative stress induced
by maternal hyperglycemia, but do not constitute an effective barrier against ROS, which
are elevated and affect both the placental fetal side and the developing fetus.