Biomedical subjects

M Castellucci

Publications and source records attributed to M Castellucci.

At least 19 recordsLinked to original sources

PubMed2005

Growth factors and their receptors: fundamental molecules for human placental development.

In this review we present data concerning the localization of some important growth factors and their receptors in the human placenta. We focus our attention on molecules playing a fundamental role in angiogenesis and morphologic processes as beta-FGF, EGF and TGF-beta. The distribution of these growth factors and their receptors in the placental villi during gestation suggests that these molecules play a pivotal role in growth and differentiation of the villous tree.

Chorionic Villi↗

PubMed2004

Placental expression of substance P and vasoactive intestinal peptide: evidence for a local effect on hormone release.

The present study evaluated vasoactive intestinal peptide (VIP) and substance P (SP) mRNA expressions and the localization of both peptides in first- and third-trimester human placentas. VIP and SP mRNAs were detected by slot blot analysis in first- and third-trimester placental tissues. By immunohistochemistry both neuropeptides were localized in the trophoblast (syncytium and cytotrophoblastic cells) of the chorionic villi. Because little information is available on the role of VIP and/or SP on the secretion of placental hormones, we investigated the effect of these neuropeptides on human chorionic gonadotropin (hCG) and progesterone release from primary cultured human trophoblastic and JEG-3 cells. The addition of increasing doses of VIP resulted in a dose-dependent stimulation of hCG release from cultured human trophoblast and JEG-3 cells. Increasing doses of VIP also dose-dependently stimulated progesterone secretion from primary cultured trophoblastic cells at all time points evaluated and from JEG-3 cells only after 3 h. SP did not affect hCG and progesterone secretion either in cultured human trophoblast or in JEG-3 cells. In conclusion, the present study demonstrates that VIP and SP are mainly expressed in human trophoblasts, and that VIP modulates the in vitro secretion of hCG and progesterone, suggesting a different role in trophoblastic function of the two peptides.

Cells, Cultured↗

PubMed2003

Urokinase receptor is up-regulated in endothelial cells and macrophages associated with fibrinoid deposits in the human placenta.

Clearance of fibrin deposits within the human placenta is an ongoing process during normal placental development. Plasminogen is a circulating fibrinolytic protease zymogen activated in situ by plasminogen activators. We have previously reported that the receptor for urokinase plasminogen activator (uPAR) is expressed by cells either covering or enmeshed within the perivillous fibrinoid deposits. Whereas these cells seemed likely to be trophoblasts, a definitive identification was lacking, and this question is central to the understanding of the cellular mechanisms directing fibrinolysis in the placenta. In this study we have performed immunohistochemical co-localization studies and found that the uPAR-positive cells covering fibrinoid deposits are immunoreactive for CD31 and vWF, indicating that they are actually endothelial cells. In addition, we found that perivillous fibrinoid deposits not covered with uPAR-positive endothelial cells were covered with platelets identified by integrin alpha(IIb)beta(3)-immunoreactivity. Also surprisingly, the uPAR-positive cells enmeshed within fibrinoid deposits express a cell specific marker indicating that they are macrophages. Both uPAR-positive cell populations also express uPA immunoreactivity. Taken together, the data suggest that both fibrinoid-covering endothelial cells and fibrinoid-enmeshed macrophages can participate in the clearance process of perivillous fibrinoid deposits formed in the human placenta.

Adult↗

PubMed2002

PPARgamma expression in normal human placenta, hydatidiform mole and choriocarcinoma.

Peroxisome proliferator-activated receptor (PPAR) gamma belongs to a subclass of nuclear hormone receptors that execute their transcriptional functions as heterodimers with the retinoid X receptors (RXR). PPARgamma plays a pivotal role in cellular differentiation. This study investigated PPARgamma protein expression in normal human placentas, hydatidiform moles and choriocarcinoma, using immunohistochemical and Western blot analyses. In first trimester normal placenta, PPARgamma was mainly localized in the nuclei of the villous cytotrophoblastic cells, whereas at term it was mainly localized in the nuclei of the syncytiotrophoblast. Extravillous cytotrophoblast of cell islands and cell columns also showed nuclear PPARgamma immunostaining. A striking result was the altered expression patterns of PPARgamma in pathological tissues; PPARgamma showed a reduced immunostaining in the trophoblastic diseases. In hydatidiform moles, PPARgamma was mainly localized in the nuclei of the trophoblastic collections of the pathological villi and in the extravillous trophoblastic cells, whereas in the choriocarcinoma, only a few trophoblastic cells showed weak PPARgamma nuclear immunostaining. These findings suggest an involvement of PPARgamma in trophoblast differentiation during normal placental development. The down-regulation of PPARgamma expression in the gestational trophoblastic diseases analysed in this study provides a new insight into the progression of these pathologies.

Choriocarcinoma↗

PubMed2002

Plasminogen activator inhibitor type-1 deficiency attenuates murine antigen-induced arthritis.

OBJECTIVE: To examine the role of plasminogen activator inhibitor type-1 (PAI-1), the major fibrinolytic inhibitor, in vivo during murine antigen-induced arthritis (AIA). METHODS: AIA was induced in PAI-1-deficient mice and control wild-type mice. Arthritis severity was evaluated by technetium 99m (99mTc) uptake in the knee joints and by histological scoring. Intra-articular fibrin deposition was examined by immunohistochemistry and synovial fibrinolysis quantitated by tissue D-dimer measurements and zymograms. RESULTS: Joint inflammation, quantitated by 99mTc uptake, was significantly reduced in PAI-1(-/-) mice on day 7 after arthritis onset (P<0.01). Likewise, synovial inflammation, evaluated by histological scoring, was significantly decreased in PAI-1-deficient mice on day 10 after arthritis onset (P<0.001). Articular cartilage damage was significantly decreased in PAI-1(-/-) mice, as shown by histological grading of safranin-O staining on day 10 after arthritis onset (P<0.005). Significantly decreased synovial accumulation of fibrin was observed by day 10 in arthritic joints of PAI-1(-/-) mice (P<0.005). Accordingly, the synovial tissue content of D-dimers, the specific fibrin degradation products generated by plasmin, were increased in PAI-1(-/-) mice (P<0.02). Finally, as expected, PA activity was increased in synovial tissues from PAI-1(-/-) mice, as shown by zymographic analysis. CONCLUSIONS: These results indicate that deficiency of PAI-1 results in increased synovial fibrinolysis, leading to reduced fibrin accumulation in arthritic joints and reduced severity of AIA.

Animals↗

PubMed2001

Sema3a is produced by brown adipocytes and its secretion is reduced following cold acclimation.

Heat production in brown adipose tissue (BAT) and brown adipocyte recruitment depend heavily on BAT vascular and parenchymal sympathetic and sensory innervation. The expression and distribution of Sema3a, a recently discovered chemorepellent neuronal factor active on both sympathetic and sensory peripheral nerves, were studied in interscapular rat BAT. In rats maintained in thermoneutral conditions, brown adipocytes produced both active isoforms of Sema3a and showed a distinct peripheral polarized immunostaining pattern. This suggests a role for Sema3a secreted by brown adipocytes in the guidance of axons toward their correct targets. In cold-acclimated rats, where parenchymal nerve density is higher, both the expression and the immunostaining of the two active isoforms were slightly but significantly reduced and the distinct staining pattern was not observed. These data suggest that the secretion of Sema3a is inhibited in the brown adipocytes of cold-acclimated rats. Thus, Sema3a could play a role in the plastic adjustment of BAT innervation observed in different conditions of functional demand.

Acclimatization↗

PubMed2001

Expression of ZO-1 and occludin in normal human placenta and in hydatidiform moles.

Zonula occludens-1 (ZO-1) and occludin are key molecules in cell-cell contacts. They are tight junction constituents and therefore play a pivotal role in tissue differentiation and organogenesis. In the present report we have investigated the expression of ZO-1 and occludin in normal human placentae and in hydatidiform moles using immunohistochemical and Western blot analyses. In normal placentae, ZO-1 and occludin were mainly localized in the apical part of the syncytium, in cell-cell contacts between syncytium and villous cytotrophoblastic cells as well as between the latter. Extravillous cytotrophoblast of cell islands and cell columns was positive for ZO-1 and occludin in the cell layers proximally located to the villous stroma whereas the cytotrophoblastic cells, distally located from the villous stroma, were totally negative. Furthermore, fetal vessels showed a positive staining pattern for ZO-1 throughout gestation, whereas a positive reaction for occludin was produced mainly at term. A striking result was the altered expression of ZO-1 and occludin in partial and complete moles. In 11 moles, these two molecules were not expressed at all, while in the other nine, their expression was only cytoplasmic in syncytium and villous cytotrophoblastic cells. These findings suggest that ZO-1 and occludin participate in normal placental development, maintaining the organization and functions of different tissue components. The down-regulation and/or dysregulation of these two molecules may be related to phenotypic changes associated with epithelial cell transformation of the chorionic villi in partial and complete moles.

Blotting, Western↗

PubMed2001

Hyaluronate and CD44 expression patterns in the human placenta throughout pregnancy.

Hyaluronan (HA) and CD44 are involved in several processes such as cell migration and differentiation. In the present study, we examined the expression and distribution of both hyaluronan and its cell surface receptor (CD44) in the human placenta, which is a rapidly growing and differentiating organ that plays a fundamental role in fetal life. Hyaluronan was detected by a specific biotinylated binding probe, termed b-PG. In the first half of gestation, HA was strongly expressed in the stroma of the mesenchymal villi which have been previously identified as responsible for the growth and differentation of the villous trees. The other villous types showed an intense staining only in the fetal vessel walls and in the connective tissue closely underlying the trophoblastic cover. In addition, hyaluronan positive staining was also apparent in a restricted rim of villous stroma directly apposed to extravillous cytotrophoblastic cell islands and cell columns. In full term placentas, all villi expressed HA in their stromal tissue with a more homogenous staining than in the first half of gestation. In contrast to hyaluronan, in the first trimester CD44 was restricted to some of the Hofbauer cells which may be able to internalize hyaluronan, thus playing a significant role in its removal in early pregnancy. CD44 was primarily expressed starting from the 16th week of gestation. At the end of pregnancy it was expressed in the various villous types, especially in stem villi. Moreover, the plasma membrane of some extravillous cytotrophoblastic cells in the basal plate and the large majority of the decidual cells showed a positive immunostaining for this receptor. Taken together, these data suggest that HA is strongly involved in early villous morphogenesis, whereas CD44 seem to be play an important role in tissue remodelling later in gestation.

Female↗

PubMed2000

Leptin modulates extracellular matrix molecules and metalloproteinases: possible implications for trophoblast invasion.

Leptin is a circulating hormone which plays an important role in the regulation of energy balance, haemopoiesis and reproduction. Leptin and its receptor (leptin-R) are localized in human placental tissue but their function is not known. In this study we have investigated the expression of leptin and leptin-R in the human placenta with particular attention to extravillous cytotrophoblastic cell islands and cell columns which play a pivotal role in trophoblast invasion and placental growth. We demonstrate that leptin-R immunoreactivity shows a strong expression in the distal extravillous cytotrophoblastic cells of cell columns invading the basal plate, whereas leptin expression is homogeneously expressed in all the cellular components of cell columns. Since the invasive ability of the distally located extravillous cytotrophoblast of cell columns is known to be regulated by a variety of proteases and some extracellular matrix molecules, we tested the influence of leptin on the in-vitro production of matrix metalloproteinase (MMP)-2, MMP-9 and fetal fibronectin (fFN) by cytotrophoblastic cells. We demonstrate that leptin increases, in a dose-dependent manner, the secretion of immunoreactive MMP-2 and fFN and enhances the activity of MMP-9 in cultured cytotrophoblastic cells. Our results suggest that leptin and leptin-R could have a role in the invasive processes of the extravillous cytotrophoblastic cells by modulating the expression of MMPs. In addition, these results provide a foundation for studying pathological conditions characterized by insufficient or excessive trophoblast invasion.

Carrier Proteins↗

PubMed1999

Expression pattern alterations of syndecans and glypican-1 in normal and pathological trophoblast.

Syndecans (syn-1, -2, -3, -4) and glypican-1 are proteoglycans expressed during development in association with changes in tissue organization and differentiation. They participate in the modulation of growth factor actions and in cell-cell and cell-matrix adhesion. The expression of syn-1, -2, -3, -4, and glypican-1 has been studied in normal human placenta and in gestational trophoblastic disease such as hydatidiform mole, invasive mole, and choriocarcinoma, using immunohistochemistry and western blots. Syndecan-3 was not expressed in normal or pathological tissues. During normal gestation, the other proteoglycans showed a specific staining pattern, which for some was modified during pregnancy. For instance, syn-1 was only expressed in syncytiotrophoblast; syn-4 was mainly localized in the villous and extravillous cytotrophoblast in the first trimester, whereas at term it was expressed in the syncytiotrophoblast. The most striking results are the altered expression patterns of syndecans and glypican-1 in pathological tissues. These proteoglycans showed a progressive decrease of immunostaining related to the increase of severity of trophoblastic disease, in particular in invasive mole and choriocarcinoma. In addition, dysregulation in the localization of the expression patterns was observed for syn-2 and -4. Because changes in syndecan expression enable cells to become more or less responsive to their micro-environment, the down-regulation and/or dysregulation of syndecans in relation to the degree of severity of trophoblastic diseases provides new insights into the progression of these pathologies.

Blotting, Western↗

PubMed1998

Lack of insulin receptors affects the formation of white adipose tissue in mice. A morphometric and ultrastructural analysis.

Lack of insulin receptors in mice is associated with near-normal intrauterine growth, unlike patients with leprechaunism, in whom growth deficiency is a prominent clinical feature. Genetic crosses of insulin receptor- and insulin-like growth-factor-1 (IGF-1) receptor-deficient mice indicate, however, that insulin receptors play an important role in late gestational growth, and that absence of growth retardation in insulin receptor-deficient (IR-/-) mice may be due to a compensatory increase in IGF-1 receptor levels. In human fetuses, insulin has a paramount role in the generation and maintenance of adipose tissue, as demonstrated by changes associated with genetic and maternally caused fetal hyperinsulinaemia. In the present study, we have investigated whether genetic ablation of insulin receptors affects differentiation and trophism of white adipose tissue, the main target organ for the growth-promoting actions of fetal insulin. Histological, immunohistochemical, and ultrastructural analyses of white dermal adipose tissue were performed in newborn IR-/- mice, as well as normal (IR +/+ ) and heterozygous controls (IR+/-). Stereological measurements revealed a marked decrease of the adipose area in IR-/- mice compared to IR+/+ and IR+/- mice. Fat cell depletion resulted mainly from a reduction of adipocyte volume ( approximately 90 %), with a small decrease of adipocyte number. Electron microscopy analysis detected all stages of differentiation of the adipocyte precursor in IR-/- mice, suggesting that lack of insulin receptors is not associated with selective impairment of the adipocyte differentiation process. These data are consistent with a bi-modal action of fetal insulin receptors, one to mediate embryonic growth in response to IGF-2, and one to mediate adipose cell formation in response to insulin.

Adipose Tissue↗

PubMed1998

Immunohistochemical identification of the receptor for urokinase plasminogen activator associated with fibrin deposition in normal and ectopic human placenta.

The receptor for urokinase plasminogen activator (uPAR) is a key molecule in cell surface-directed plasminogen activation. uPAR binds urokinase plasminogen activator (uPA) and thereby focuses plasminogen activation on the cell surface. Plasmin dissolves fibrin deposits and facilitates cell migration during tissue repair processes by degrading the extracellular matrix. During human implantation and placental development, plasmin is considered important for both trophoblast migration/invasion and for fibrin surveillance. This study examined the expression of uPAR in normal and ectopic human placentae by immunohistochemistry. In first and third trimester normal placentae as well as in tubal ectopic placental tissues, a high uPAR expression was seen in the trophoblast associated with deposits of fibrin-type fibrinoid. Extravillous trophoblast of the basal plate, of the cell islands, and of the cell columns was also positive for uPAR in the first trimester whereas at term the expression of the protein was decreased. Moreover, uPAR immunostaining was observed in decidual cells throughout normal gestation and in endometrial tissues of patients with ectopic pregnancies. These findings suggest that uPAR participates in placental development and in trophoblast invasion particularly in the first trimester of pregnancy and that uPAR is involved in repair mechanisms of the trophoblast and fibrin surveillance.

Adult↗

PubMed1998

BCL-2 expression in the human placenta and its correlation with fibrin deposits.

The human placenta performs numerous functions during its limited lifespan and its survival is a necessary prerequisite for fetal nutrition, even in unfavourable conditions. BCL-2 is a proto-oncogene implicated in the regulation of cell death and survival without affecting cell proliferation. An extracellular matrix molecule involved in the reparative and degenerative processes in the human placenta is fibrin. We have analysed by immunohistochemistry the expression of BCL-2 and correlated it with fibrin deposits in placental tissues. In first and third trimester placentas BCL-2 was expressed in the syncytiotrophoblast. Only a few mesenchymal villi (first trimester) or terminal villi (third trimester) showed no staining in the syncytiotrophoblast. Villous cytotrophoblast, mesenchymal cells of the villous cores and extravillous cytotrophoblast of cell columns and cell islands were all negative for BCL-2. BCL-2 expression was enhanced in the syncytiotrophoblast overlying subtrophoblastic fibrin deposits. However, discontinuities and/or variations in intensity of BCL-2 expression characterized not only the villi showing perivillous fibrinoid but also those villi with a massive presence of fibrinoid in their cores. These data suggest that BCL-2 may be necessary for the preservation of the placenta during gestation as well as for the reparative processes of the trophoblast.

Female↗

PubMed1998

Fibronectins and basal lamina molecules expression in human subcutaneous white adipose tissue.

Adipose tissue is a type of connective tissue whose extracellular matrix (ECM) components are poorly characterized in vivo. Several in vitro studies have suggested a regulatory role for the ECM molecules during adipocyte differentiation. Since no data are available concerning the in vivo expression of the main ECM components such as fibronectin, collagen IV, laminin and heparan sulfate proteoglycan in the adipose tissue, we investigated the presence of these molecules by immunohistochemistry. We show that fibronectin isoforms are not expressed in fully differentiated subcutaneous adipocytes whereas collagen IV, laminin and heparan sulfate are detectable around single adipocytes, i.e. in the region corresponding to the basement membrane. These data are supported by previous in vitro studies showing a strong decrease of fibronectin synthesis during adipocyte development whereas basement membrane molecules seem to increase during adipocyte differentiation.

Adipose Tissue↗

PubMed1996

Cloning of choriocarcinoma cells shows that invasion correlates with expression and activation of gelatinase A.

Implantation and placental development are dependent upon trophoblast invasion of the endometrium. While the villous trophoblast does not display invasive behavior, the extravillous cytotrophoblast is highly invasive. By cloning BeWo choriocarcinoma cells, we have isolated two distinct clones that share similarities with villous and extravillous cytotrophoblasts. When cultured at the surface of a type I collagen gel, BeWo MC-1 cells were not invasive, whereas BeWo MC-2 cells rapidly invaded this matrix. When injected subcutaneously in nude mice, BeWo MC-1 cells developed a localized tumor and BeWo MC-2 cells developed larger tumors with micrometastases. Gelatinase A expression and minute amounts of gelatinase B were detected in the parental cell line and in both clones. However, the parental and the BeWo MC-2 cells secreted 5-to 10-fold more gelatinase A than the BeWo MC-1 cells. Laminin and matrigel stimulated the production of gelatinase A in BeWo MC-2 cells. Type I collagen promoted the conversion of the 72-kDa progelatinase A in an active enzyme only in parental BeWo and in BeWo MC-2 cells. These clones provide an interesting model for studying the complex mechanisms regulating implantation as well as the controlled invasiveness during implantation compared to tumor invasion.

Animals↗

PubMed1996

Codistribution of basic fibroblast growth factor and heparan sulfate proteoglycan in the growth zones of the human placenta.

In order to obtain an insight into morphogenetic processes such as angiogenesis, cell proliferation, and tissue remodeling we have studied the localization of basic fibroblast growth factor (bFGF) and heparan sulfate proteoglycan (HSPG) in the human placenta by immunohistochemistry. Positive reaction product for bFGF is found mainly in the villous trophoblastic covering and for HSPG in the villous basement membranes. A codistribution of the two molecules is detectable in first trimester placental tissue, in areas previously identified as being responsible for the growth of the villous tree, i.e., in the mesenchymal villi and the cytotrophoblastic cell islands and cell columns, both consisting of extravillous trophoblast. HSPG and bFGF are codistributed in the distal half of the villous stroma in the mesenchymal villi. In cell islands and cell columns, bFGF is detectable in the cytoplasm of the extravillous cytotrophoblastic cells, whereas HSPG is localized between the extravillous cytotrophoblastic cells and in their cytoplasm. HSPG-bFGF codistribution in term placenta is confined to the walls of fetal vessels and to some extravillous cytotrophoblastic cells in the basal plate. The codistribution of bFGF and HSPG in first trimester placental tissue suggests that these two molecules play a pivotal role in the morphogenetic processes mentioned above in early stages of gestation.

Chorionic Villi↗

PubMed1995

The monoclonal antibody GB 42--a useful marker for the differentiation of myofibroblasts.

The expression patterns of a variety of cytoskeletal antigens were studied in normal human tissues (placenta, umbilical cord, myometrium, colon, mammary gland, testis, skeletal muscle, myocardium) as well as in abnormal human tissues (palmar fibromatosis, fibrocystic disease of the mammary gland, mammary carcinoma). The immunohistochemical binding patterns of the monoclonal antibody GB 42 were compared to those of commercial antibodies directed against vimentin, desmin, smooth muscle myosin, pan actin, alpha-smooth muscle actin and gamma-smooth muscle actin. Methods applied comprised immunohistochemistry on cryostat sections and paraffin sections. Immunogold immunocytochemistry was performed on Lowicryl sections. The patterns of GB 42-binding were confirmed biochemically by SDS-PAGE and Western-blotting, and quantitative amino acid analysis. Our data suggest that the monoclonal antibody GB 42 recognizes an actin isoform which is identical to, or closely related to, gamma-smooth muscle actin. Unlike the commercially available antibody against gamma-smooth muscle actin, GB 42 does not cross-react with alpha-skeletal or alpha-cardiac actins. The GB 42-antigen is expressed in smooth muscle cells, myoepithelial cells and in later stages of differentiation of myofibroblasts, in all the tissues investigated. Throughout the development of smooth muscle cells and myofibroblasts, the appearance of the GB 42-antigen occurs after the expression of vimentin, desmin and alpha-smooth muscle actin, but prior to the expression of smooth muscle myosin. GB 42 is a reliable marker for higher stages of differentiation of smooth muscle cells and myofibroblasts.

Amino Acids↗

PubMed1995

Differentiation of human trophoblast populations involves alterations in cytokeratin patterns.

Cytokeratins (CKs) are related to proliferation and differentiation of epithelial cells. Little knowledge exists about CK patterns in human trophoblast subpopulations (villous and extravillous trophoblasts). To better understand differentiation and function of trophoblast components, we studied the distribution patterns of CKs in the placenta throughout pregnancy. A panel of well-defined monoclonal antibodies against different types of cytokeratins, vimentin, and fibrin, was used on frozen and paraffin sections. CK8, 18, and 19 were expressed in all the villous and extravillous trophoblastic subsets throughout pregnancy. In the first trimester, syncytiotrophoblasts were positive for CK7 and 13 along the basal membrane. As pregnancy progressed there was an increase in intensity of the reaction product and a more diffuse positive staining of CK7 in the cytoplasm of the syncytium, with evident positivity along the apical membrane. CK13 showed similar expression as CK7, but with less intense staining along the apical membrane and less prominent staining in the cytoplasm. Villous cytotrophoblasts were also positive for CK7 and CK13. CK17 was found related to cytotrophoblastic cells in contact with or next to fibrin deposits. Extravillous cytotrophoblasts in cell islands and cell columns were positive for CK13 only in the cell layers located proximal to the villous stroma, whereas the distal and more differentiated cells were negative. CK7 was positive in all epithelial cells of cell islands and columns, but the reaction product was not present in cells deeply migrated into the decidua. Amnion was negative for anti-CK13 antibodies in the first trimester but was positive at term. CK4 and CK16 were not found in the placenta. Our study shows for the first time that the different populations of human placental trophoblast express cytokeratins in developmental, differentiative, and functional specific patterns. These findings can be useful to distinguish and classify the various trophoblastic populations and provide a foundation for studying pathological aspects of the trophoblast.

Cell Differentiation↗