Decrease of elastic tissue fibres in stem villus blood vessels of the human placenta during IUGR and IUGR with concomitant pre-eclampsia

Abstract

In a recent study we described an increase of elastic tissue fibres in blood vessel walls of placental stem villi during pre-eclampsia when compared to uncomplicated pregnancies. Furthermore, the thickness of these blood vessel walls was enhanced in pre-eclampsia. Since it is known that elastic tissue fibres increase in systemic hypertension, it may be assumed that the enhancement of elastic tissue fibres in placental stem villi during pre-eclampsia may be induced by the hypertension. To get further insight into this assumption, we examined the amount of elastic tissue fibres in stem villus blood vessels of placentae of pregnancies complicated by intrauterine growth retardation (isolated IUGR, fourteen cases), a disease without hypertension of the mother and such with pre-eclampsia and concomitant IUGR (IUGR+PE, nine cases). Each study group was compared with uncomplicated pregnancies (twenty-six cases). Unfixed cryostat serial sections were processed for conventional orcein staining and for the demonstration of alpha-actin-immunoreactivity. The intensity of orcein staining of stem villus blood vessel walls was evaluated by a semiquantitative score method. Significant lower intensities of orcein staining were calculated for blood vessel walls of placentae of isolated IUGR (P=0.0007) and IUGR+PE (P=0.0039) when compared to uncomplicated pregnancies each. Additionally, the blood vessel wall thickness of stem villi of isolated IUGR (P=0.0081) and IUGR+PE (P=0.0007) was significantly reduced. In comparison to the above mentioned investigation, our results show that, in contrast to isolated pre-eclampsia, elastic tissue fibres are decreased during pregnancies complicated by IUGR, independently of the occurrence of concomitant pre-eclampsia when compared to uncomplicated pregnancies. From our studies it may be considered that the increase of elastic tissue fibres in placentae of patients with isolated pre-eclampsia may be induced by systemic hypertension. Furthermore, our study underline arguments that IUGR may be an independent disease of the fetus.

Developmental Indices of Nutritionally Induced Placental Growth Restriction in the Adolescent Sheep

“…bcl-2 and p53 (16,17,31), and histopathologic changes including alterations in stem villus blood vessels and elongated terminal villi (18,32,33). Two mechanisms have been proposed to explain these observations.…”

Altered proteome profiles in maternal plasma in pregnancies with fetal growth restriction

“…Clinically significant FGR is caused by reduced fetal growth resulting from maternal conditions such as undernutrition, smoking, drugs, and prepregnancy or pregnancy diseases, that include chronic hypertension or preeclampsia (8). Although the etiology and pathophysiology of FGR may be varied (2), it is widely accepted that poor placental development and or placental disease is the major common factor that is associated with abnormal fetal growth (8,9). Once congenital infection and chromosomal or congenital anomalies have been ruled out, FGR is mostly a result of uteroplacental insufficiency (10).…”

Analysis of placenta vascularization in patients with uterine altered artery Doppler flow velocity exams

“…Wilhelm et al. 12 observed a greater thickness in stem villi vessel walls associated with a greater quantity of elastic fiber in patients with pre‐eclampsia. These findings were attributed to an increase in maternal and/or fetal blood pressure, accompanied by stem villi wall damage responsible for the proliferation and activation of smooth muscular cells, which possess a great response capacity to physiological and pathological stress.…”

“…Alterations in placental stem villi walls are observed in patients with diabetes, Rh-immunization, stillborns and maternal hypertension, which may reflect a fetal hemodynamic response, represented by an increase in fetal blood pressure in response to low blood flow. 11 Wilhelm et al 12 observed a greater thickness in stem villi vessel walls associated with a greater quantity of elastic fiber in patients with pre-eclampsia. These findings were attributed to an increase in maternal and/or fetal blood pressure, accompanied by stem villi wall damage responsible for the proliferation and activation of smooth muscular cells, which possess a great response capacity to physiological and pathological stress.…”