Fetal growth restriction (FGR) results from placental insufficiency to adequately supply the fetus. This insufficiency involves impaired cytotrophoblast functions, including reduced migration and invasion, proliferation, and syncytium formation. Membrane-type matrix metalloproteinase 1 (MT1-MMP) is a key enzyme in these cellular processes.
View Article and Find Full Text PDFThe placental endothelium is unique among the entire human vasculature. The blood enriched in oxygen and nutrients is transported in the veins, whereas the arteries contain deoxygenated blood coming from the fetus. The placental vasculature has to develop rapidly to ensure adequate supply of the fetus.
View Article and Find Full Text PDFThe mouse mutant wavy tail Tg(Col1a1-lacZ)304ng was created through transgene insertion and exhibits defects of the vertebral column. Homozygous mutant animals have compressed tail vertebrae and wedge-shaped intervertebral discs, resulting in a meandering tail. Delayed closure of lumbar neural arches and lack of processus spinosi have been observed; these defects become most prominent during the transition from cartilage to bone.
View Article and Find Full Text PDFGrowing interest in the sources of origin of blood vessel related diseases has led to an increasing knowledge about the heterogeneity and plasticity of endothelial cells lining arteries and veins. So far, most of these studies were performed on animal models. Here, we hypothesized that the plasticity of human fetal endothelial cells depends on their vascular bed of origin i.
View Article and Find Full Text PDFSeveral clinical situations require continuous glucocorticoid (GC) treatment during pregnancy. A well-known deleterious side effect of such treatment is the higher incidence of growth-restricted fetuses, for which a too shallow trophoblast invasion is presently hypothesised as the underlying cause. This study investigated whether the synthetic GC triamcinolone acetonide (TA) influences proliferation, invasion and endocrine activity of human trophoblast.
View Article and Find Full Text PDFAims/hypothesis: The human placenta is a complex organ situated at the interface between mother and foetus that separates maternal from foetal blood. The placental surfaces exposed to the two bloodstreams are different, i.e.
View Article and Find Full Text PDFPKCdelta has been implicated in the signalling events after engagement of the antigen specific receptor on B cells and the Fc-epsilon receptor on mast cells. Employing our recently established PKCdelta null mice , we here investigate the physiological function of PKCdelta in CD3+ T cells. As result, administration of anti-CD3 antibodies in vivo induced markedly increased blood plasma IL-2 levels (but not IL-4, IFN-gamma, TNF-alpha and IL-6 levels) in the PKCdelta null mice, when compared to wild-type sibling controls.
View Article and Find Full Text PDFTrophoblast invasion of the uterine extracellular matrix, a critical process of human implantation and essential for fetal development, is a striking example of controlled invasiveness. To identify molecules that regulate trophoblast invasion, mRNA signatures of trophoblast cells isolated from first trimester (high invasiveness) and term placentae (no/low invasiveness) were compared using U95A GeneChip microarrays yielding 220 invasion/migration-related genes. In this 'invasion cluster', KiSS-1 and its G-protein-coupled receptor KiSS-1R were expressed at higher levels in first trimester trophoblasts than at term of gestation.
View Article and Find Full Text PDFWe have characterized a 185-kb contig surrounding a transgene on distal mouse chromosome 11, the insertion of which has caused a recessive phenotype with skeletal malformations. By cDNA selection and sequencing we have found six genes (Lasp1, Rpl23, Mllt6, Pip5k2b, Psmb3, Zfp144), one truncated gene (Mel13), and one pseudogene (Rps15-ps) within this region. The murine Mllt6 gene is new, it was identified by its high homology (90% identity) with the human homologue MLLT6.
View Article and Find Full Text PDFJ Matern Fetal Neonatal Med
April 2002
Fetal macrosomia may occur even in adequately controlled diabetic mothers. This may reflect the problem of using maternal glycemia as an indicator of fetal glycemia, because the placenta interposed between both compartments has its own glucose metabolism. Here, we propose a model by which the placenta protects the fetus at moderate levels of maternal hyperglycemia.
View Article and Find Full Text PDFThe ubiquitously expressed Na(+)/H(+) exchanger (NHE1) plays an important role in the regulation of the intracellular pH. Induction of NHE activity by phorbol esters and inhibition of growth factor-mediated stimulation of the NHE by protein kinase C (PKC) inhibitors suggest an implication of PKCs in the regulation of the NHE. Expression of PKC isotype-specific dominant negative and constitutively active mutants or downregulation of PKC by isotype-specific antisense oligonucleotides revealed that stimulation by epidermal growth factor (EGF) or phorbol ester of the NHE in NIH3T3 cells is a PKC(alpha)-specific effect.
View Article and Find Full Text PDFSmooth muscle cell (SMC) accumulation is a key event in the development of atherosclerosis, including vein bypass graft arteriosclerosis. Because members of the protein kinase C (PKC) family signal cells to undergo proliferation, differentiation, or apoptosis, we generated PKCdelta knockout mice and performed vein bypass grafts on these animals. PKCdelta(-/-) mice developed normally and were fertile.
View Article and Find Full Text PDFProtein kinase C (PKC)-θ, a serine/threonine protein kinase and novel PKC subfamily member, has been recently identified as an essential component of the T cell synapse which activates the NF-kB signaling cascade leading to expression of the IL-2 gene during T cell activation. By RNA in situ hybridization to whole-body embryo sections it is shown that the murine PKCθ is specifically expressed in tissues with hematopoietic and lymphopoietic activity. Expression is also evident in skeletal muscle.
View Article and Find Full Text PDFT lymphocyte stimulation leading to interleukin-2 (IL-2) expression requires activation of protein kinase C (PKC); however, the relevant PKC isoform(s) have not yet been systematically defined. Here we examine seven major T cell expressed PKC isoforms (PKCalpha, delta, epsilon, zeta, nu, theta and iota) and identify PKCtheta to be essential for IL-2 expression (via the critical NF-AT and NF-kappaB enhancer) in Jurkat T cells. Employing a conditionally activated PKCtheta estrogen-receptor fusion mutant, a de novo synthesis-independent transactivation of JNK2 was established.
View Article and Find Full Text PDFDeletion of activated peripheral T cell clones by apoptosis requires the regulated expression of Fas ligand (FasL) and sensitization of these cells to CD95-mediated signaling. To investigate the signaling pathways responsible for FasL expression in T cells, we tested-besides subfamily-selective protein kinase C (PKC) inhibitors - the effect of constitutively active mutants of representatives of all PKC subfamilies, i.e.
View Article and Find Full Text PDFArterioscler Thromb Vasc Biol
August 1999
Low density lipoprotein (LDL) is a well-established risk factor for atherosclerosis, stimulating vascular smooth muscle cell (SMC) differentiation and proliferation, but the signal transduction pathways between LDL stimulation and cell proliferation are poorly understood. Because mitogen-activated protein kinases (MAPKs) play a crucial role in mediating cell growth, we studied the effect of LDL on the induction of MAPK phosphatase-1 (MKP-1) in human SMCs and found that LDL stimulated induction of MKP-1 mRNA and proteins in a time- and dose-dependent manner. Heparin, inhibiting LDL-receptor binding, did not influence LDL-stimulated MKP-1 mRNA expression, and human LDL also induced MKP-1 expression in rat SMCs and fibroblasts derived from LDL receptor-deficient mice, indicating an LDL receptor-independent process.
View Article and Find Full Text PDFThe predominant expression of protein kinase C (PKC) theta in T cells (J. Biol. Chem.
View Article and Find Full Text PDFCell type-specific differences in the transcriptional control of the mouse gene coding for the alpha 1 chain of collagen type I (Col1a1) have been revealed previously with the help of the Mov13 mouse strain which carries a retroviral insert in the first intron of the gene. Transcription of this mutant Col1a1 allele is completely blocked in all mesodermal cell types tested so far, with the exception of the odontoblast where it is expressed at an apparently normal rate (Kratochwil et al. [1989] Cell 57:807-816).
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