ABSTRACT
Prenatal stress (PS) can cause early and long-term developmental effects resulting in part from altered maternal and/or fetal glucocorticoid exposure. The aim of the present study was to assess the impact of chronic restraint stress during late gestation on feto-placental unit physiology and function in embryonic (E) day 21 male rat fetuses. Chronic stress decreased body weight gain and food intake of the dams and increased their adrenal weight. In the placenta of PS rats, the expression of glucose transporter type 1 (GLUT1) was decreased, whereas GLUT3 and GLUT4 were slightly increased. Moreover, placental expression and activity of the glucocorticoid "barrier" enzyme 11beta-hydroxysteroid dehydrogenase type 2 was strongly reduced. At E21, PS fetuses exhibited decreased body, adrenal pancreas, and testis weights. These alterations were associated with reduced pancreatic beta-cell mass, plasma levels of glucose, growth hormone, and ACTH, whereas corticosterone, insulin, IGF-1, and CBG levels were unaffected. These data emphasize the impact of PS on both fetal growth and endocrine function as well as on placental physiology, suggesting that PS could program processes implied in adult biology and pathophysiology.
Subject(s)
Endocrine Glands/embryology , Placenta/metabolism , Pregnancy Complications/metabolism , Stress, Physiological/metabolism , 11-beta-Hydroxysteroid Dehydrogenase Type 2/metabolism , Adrenal Glands/pathology , Animals , Blood Glucose/metabolism , Body Weight , Chronic Disease , Eating , Female , Fetal Blood/metabolism , Fetus/anatomy & histology , Fetus/metabolism , Glucose Transport Proteins, Facilitative/metabolism , Hormones/blood , Insulin-Secreting Cells/cytology , Islets of Langerhans/embryology , Male , Organ Size , Pancreas/embryology , Pregnancy , Pregnancy Complications/pathology , Pregnancy Complications/physiopathology , Rats , Restraint, Physical , Stress, Physiological/etiology , Stress, Physiological/pathology , Stress, Physiological/physiopathology , Testis/embryologyABSTRACT
The present study compares some phenotypic and physiologic characteristics of microvascular and macrovascular endothelial cells from within one human organ. To this end microvascular endothelial cells from human full-term placenta (PLEC) were isolated using a new method and compared with macrovascular human umbilical vein endothelial cells (HUVEC) and an SV40-transformed placental venous endothelial cell line (HPEC-A2). PLEC were isolated by enzymatic perfusion of small placental vessels, purified on a density gradient and cultured subsequently. Histological sections of the enzyme-treated vessels showed a selective removal of the endothelial lining in the perfused placental cotyledons. The endothelial identity of the cells was confirmed by staining with the endothelial markers anti-von Willebrand factor, Ulex europaeus lectin and anti-QBEND10. The cells internalized acetylated low-density lipoprotein and did not show immunoreactivity with markers for macrophages, smooth muscle cells and fibroblasts. The spindle-shaped PLEC grew in swirling patterns similar to that described for venous placental endothelial cells. However, scanning electron microscopic examination clearly showed that PLEC remained elongated at the confluent state, in contrast to the more polygonal phenotype of HPEC-A2 and HUVEC that were studied in parallel. The amount of vasoactive substances (endothelin-1,2, thromboxane, angiotensin II, prostacyclin) released into the culture medium and the proliferative response to cytokines was more similar to human dermal microvessels (MIEC) derived from non-fetal tissue than to HUVEC. Potent mitogens such as vascular endothelial growth factors (VEGF121, VEGF165) and basic fibroblast growth factor (FGF-2) induced proliferation of all endothelial cell types. Placental growth factors PIGF-1 and PIGF-2 effectively stimulated cell proliferation on PLEC (142 +/- 7% and 173 +/- 10%) and MIEC (160 +/- 20% and 143 +/- 28%) in contrast to HUVEC (9 +/- 8% and 15 +/- 20%) and HPEC-A2 (15 +/- 7% and 24 +/- 6%) after 48 h incubation time under serum-free conditions. These data support evidence for (1) the microvascular identity of the isolated PLEC described in this study, and (2) the phenotypic and physiologic heterogeneity of micro- and macrovascular endothelial cells within one human organ.
Subject(s)
Endothelium, Vascular/cytology , Placenta/cytology , 6-Ketoprostaglandin F1 alpha/biosynthesis , Angiotensin II/biosynthesis , Cell Division/drug effects , Cells, Cultured , Culture Media, Conditioned/chemistry , Cytokines/pharmacology , Endothelium, Vascular/chemistry , Endothelium, Vascular/metabolism , Female , Humans , Microscopy, Electron, Scanning , Placenta/ultrastructure , Poly(ADP-ribose) Polymerases/biosynthesis , Pregnancy , Proliferating Cell Nuclear Antigen/biosynthesis , Thromboxane B2/biosynthesis , Umbilical Veins/cytologyABSTRACT
PROBLEM: The scarce data on glucose transporter expression of leukocytes are contradictory and nothing is known about changes accompanying physiological leukocytosis during pregnancy, which imposes acute metabolic demands on the cells. METHOD OF STUDY: Cytospin preparations of intravascular leukocytes were searched immunocytochemically for the high affinity glucose transporters GLUT1, 3 and 4. Pregnancy-associated quantitative changes in transporter expression were assessed by flow cytometry. RESULTS: Granulocytes and monocytes stained for GLUT1, 3 and 4. Major changes in cell surface transporter expression during pregnancy were a 36% (P < 0.05) down-regulation of granulocyte GLUT1 at term, and an increase in monocyte GLUT3 levels to 137% (P < 0.05), paralleled by a 24% (P < 0.05) decrease in GLUT4 content in second trimester. Apart from a minor subpopulation, lymphocytes were negative for these carriers. CONCLUSION: GLUT1, 3 and 4 are abundantly expressed in granulocytes and monocytes. The particular isoforms are differentially regulated during pregnancy, suggesting an individual functional significance.
