13 research outputs found
Membrane-type matrix metalloproteinase 1 regulates trophoblast functions and is reduced in fetal growth restriction
No full textFetal 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. MT1-MMP exists in various forms: a 63-kDa proenzyme is synthesized as primary translation product, which is cleaved into a 57-kDa membrane-anchored active form. We hypothesized that reduced placental MT1-MMP in FGR impairs trophoblast functions. MT1-MMP mRNA and active enzyme was quantified in placentas from FGR and age-matched control pregnancies. MT1-MMP protein was localized in first-trimester and term placentas. Putative MT1-MMP functions in trophoblasts were determined using two blocking antibodies for measuring migration and proliferation, as well as fusion of primary trophoblasts and trophoblast-derived cells. MT1-MMP was expressed predominantly in the syncytiotrophoblast and the villous and extravillous cytotrophoblasts. In FGR placentas, levels of MT1-MMP mRNA and of active MT1-MMP protein were reduced (-34.2%, P < 0.05, and -21.5%, P < 0.01, respectively), compared with age-matched controls. MT1-MMP-blocking antibodies diminished migration, proliferation, and trophoblast fusion. We conclude that reduced placental MT1-MMP in FGR may contribute to the impaired trophoblast functions associated with this pathology. Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved
Endothelin/endothelin receptor system is upregulated in preeclampsia with or without fetal growth restriction in contrast to gestational diabetes
No full text
Placental fractalkine is up-regulated in severe early-onset preeclampsia
No full textThe pathogenesis of preeclampsia (PE) includes the release of placental factors into the maternal circulation, inducing an inflammatory environment in the mother. One of the factors may be the proinflammatory chemokine fractalkine, which is expressed in the syncytiotrophoblast of human placenta, from where it is released into the maternal circulation by constitutive shedding. We examined whether placental fractalkine is up-regulated in severe early-onset PE and whether the proinflammatory cytokines tumor necrosis factor (TNF)-{alpha} and IL-6 are able to increase the expression of fractalkine. Gene expression analysis, enzyme-linked immunosorbent assay, and immunohistochemistry consistently showed increased fractalkine expression in placentas from severe early-onset PE, compared to gestational age-matched controls. Expression of a disintegrin and metalloproteinases 10 and 17, which convert transmembrane fractalkine into the soluble form, was significantly increased in these cases. Incubation of first-trimester placental explants with TNF-{alpha} provoked a significant increase in fractalkine expression and release of the soluble form, whereas IL-6 had no effect. TNF-{alpha}-mediated up-regulation of placental fractalkine was reversed in the presence of the aspirin-derivative salicylate, which impaired activation of NF-{kappa}B p65 in TNF-{alpha}-treated explants. On the basis of data from placental explants, we suggest that increased maternal TNF-{alpha} may up-regulate the expression and release of placental fractalkine, which, in turn, may contribute to an exaggerated systemic inflammatory response in PE
Endothelin-1 stimulates proliferation of first trimester trophoblasts via the A- and B-type receptor and invasion via the B-type receptor
No full textEndothelin-1 Stimulates Proliferation of First-Trimester Trophoblasts via the A- and B-Type Receptor and Invasion via the B-Type Receptor
No full textAbstractContext:Endothelin-1 (ET-1) stimulates proliferation and invasion of first-trimester human trophoblast cells.Objective:To test the hypothesis that ET-1 effects are mediated by different receptor subtypes [ET receptor (ETR)-A and ETR-B].Design:The location of ETR in trophoblast cell columns (wk 6–12) was investigated by immunohistochemistry and autoradiography. Trophoblasts were isolated from first-trimester human placentas and proliferative and invasive subpopulations separated using an integrin α6 antibody. Cells were incubated for 24 h with 10 μm ET-1 and different ETR antagonists: PD142893 (unselective), BQ-610 (ETR-A), and RES-701-1 (ETR-B). After ETR down-regulation by antisense oligonucleotides, proliferation (thymidine incorporation, protein synthesis) and invasion (Matrigel invasion) were measured. ETR expression in isolated cells was analyzed by Western blotting and semiquantitative RT-PCR.Results:Both ETR are expressed in both subpopulations in the cell column with predominance of ETR-A in the proximal part and proliferative subpopulation, whereas ETR-B is present at similar levels in both subpopulations. These results were confirmed at the mRNA level. ET-1 increased proliferation (maximum 267% of control) and invasion (maximum 288% of control) of first-trimester trophoblasts. The mitogenic ET-1 effect was inhibited (P &lt; 0.05) by 40–80% with each receptor antagonist and by 44 and 40%, respectively, by ETR-A and ETR-B antisense oligonucleotides. The invasion-promoting effect was almost completely blocked in the presence of the ETR-B antagonists.Conclusion:The effect of ET-1 on cell proliferation in first-trimester trophoblasts is mediated by both ETR, whereas its effect on invasion is mediated predominantly by ETR-B. These effects are in line with the receptor subtype location.</jats:sec
Avaliação farmacológica do extrato bruto hidroalcóolico, frações e composto isolado de Cuphea carthagenensis Jacq McBrite (sete-sangrias) determinação da capacidade de antioxidante /
No full textDissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas
Platelet interaction with bioactive lipids formed by mild oxidation of low-density lipoprotein
No full textOxidation of low-density lipoprotein (LDL) generates pro-inflammatory and pro-thrombotic mediators that play a crucial role in cardiovascular and inflammatory diseases. Mildly oxidized LDL (mox-LDL) and minimally modified LDL (mm-LDL) which escape the uptake of macrophage scavenger receptors accumulate in the atherosclerotic intima. Oxidatively modified LDL is also present within the electronegative LDL fraction in blood, which is elevated in patients at high risk for cardiovascular diseases. Mox-LDL and mm-LDL, but not native LDL are able to induce platelet shape change and aggregation. LDL oxidation generates lipids with platelet stimulatory properties such as lysophosphatidylcholine, certain oxidized phosphatidylcholine molecules, F-2-isoprostanes and lysophosphatidic acid (LPA). Mox-LDL and mm-LDL are like a Trojan horse carrying these biologically active lipids and attacking cells through activation of physiological receptors and signaling mechanisms. LPA has been identified as the lipid responsible for platelet stimulation by mox-LDL, mm-LDL and also mox-HDL. These lipoproteins activate platelets by stimulating G-protein coupled LPA receptors and a Rho/Rho kinase signaling pathway leading to platelet shape change and subsequent aggregation. LPA-mediated platelet activation might contribute to arterial thrombus formation after rupture of atherosclerotic plaques and to the increased blood thrombogenicity of patients with cardiovascular diseases. Copyright (c) 2006 S. Karger AG, Basel
Ação da intervenção antioxidante na síndrome de Down
No full textTese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde, Programa de Pós-Graduação em Farmácia, Florianópolis, 2015.A Síndrome de Down (SD) é a mais frequente desordem genética humana, e é causada, na sua quase totalidade, pela trissomia do cromossomo 21. A geração excessiva de espécies reativas de oxigênio (EROs) está envolvida na patogenia da SD. O objetivo deste estudo foi (I) avaliar o status antioxidante no sangue de crianças e adolescentes SD, antes e após a suplementação com vitaminas E e C, (II) bem como o efeito da administração de melatonina (MEL) sobre os biomarcadores de estresse oxidativo (EO) e de neurogênese, em um modelo animal de SD (camundongos Ts65Dn). Biomarcadores de EO e níveis de citocinas inflamatórias foram avaliados em pacientes com SD (n=21), antes e após suplementação diária (vitamina E 400 mg, C 500 mg) durante 6 meses, seguida de interrupção da terapia (por 6 meses) e posteriormente submetidos a uma nova intervenção antioxidante de 6 meses. Crianças saudáveis (n=18) sem SD foram recrutadas para constituir o grupo controle. As atividades da superóxido dismutase (SOD), catalase (CAT), glutationa peroxidase (GPx), glutationa redutase (GR), glutationa S-transferase (GST), gama-glutamiltransferase (GGT), glicose-6-fosfato desidrogenase (G6PD) e mieloperoxidase (MPO), assim como os conteúdos de glutationa reduzida (GSH), ácido úrico (AU), vitamina E, substâncias que reagem com o ácido tiobarbitúrico (TBARS), proteína carbonilada (PC), transferrina, TNF-a e IL-1ß, foram mensuradas no sangue destes indivíduos. Antes da suplementação, os indivíduos SD, apresentaram aumento da atividade enzimática da SOD, CAT, GR, GGT e MPO, assim como dos níveis séricos de AU, transferrina, TNF-a e IL-1ß enquanto que a atividade da GST e os níveis de GSH e PC mostraram valores diminuídos. No entanto, as atividades da GPx e G6PD, assim como os níveis plasmáticos de vitamina E e TBARS, não apresentaram diferenças significativas em comparação aos controles. Após a suplementação antioxidante, as atividades das enzimas SOD, CAT, GPx, GR, GGT e MPO, bem como o conteúdo de TBARS foram diminuídos, as atividades da G6PD e GST, e os níveis de AU, PC, transferrina, TNF-a e IL-1ß permaneceram inalterados, enquanto que os conteúdos de GSH e vitamina E mostraram significativo aumento. Após a interrupção da suplementação, houve aumento das atividades da GPx e GGT nos indivíduos SD, assim como nos níveis de AU e TBARS. Nenhuma mudança foi observada nas atividades da SOD, CAT, GR, GST, G6PD e MPO, bem como nos níveis de GSH, vitamina E, PC,transferrina, TNF-a e IL-1ß. Após nova suplementação, houve aumento dos níveis plasmáticos de vitamina E e diminuição da atividade da GGT nenhuma alteração nas atividades da SOD, CAT, GPx, GR, G6PD, GST e MPO, assim como nos conteúdos de GSH, AU, transferrina, TBARS, PC, TNF-a e IL-1ß. Para o estudo da MEL foram utilizados animais jovens e adultos. Para ambas as idades, foram utilizados dois grupos de camundongos com genótipos diferentes, Controles (Dissômicos) e Ts65Dn (Trissômicos), os quais foram subdividos e tratados com veículo (água contendo 0,06% etanol) e/ou MEL (100 mg/L), formando 4 grupos experimentais: CO+Veículo, CO+Mel, TS+Veículo e TS+Mel. Para os jovens, o tratamento ocorreu desde a fase pré-natal com as fêmeas prenhas e se estenderam até a idade de experimento (5,5 meses de idade). Já para os adultos o tratamento iniciou com 5,5 e perdurou até 10,5 meses de idade. Tanto para jovens e adultos, foram avaliados biomarcadores de EO no córtex e hipocampo do cérebro desses animais. A neurogênese dos animais jovens (em adultos são dados já publicados) foi avaliada através de imunohistoquímica para Ki-67 (proteína nuclear, expressa em células em mitose) e DAPI (marcador nuclear) no hipocampo desses animais. A administração de MEL diminuiu a atividade da SOD e CAT enquanto não houve mudanças na atividade da GPx e GR e nos níveis de TBARS e PC no córtex e hipocampo. Nos animais adultos, o tratamento com a MEL diminuiu a atividade da SOD apenas no córtex, assim como os níveis de TBARS e PC no hipocampo desses animais, enquanto não houve mudanças na atividade da CAT, GPx e GR no córtex e hipocampo desses animais. Não houve mudanças na densidade de células Ki-67 e DAPI após tratamento com MEL nos animais jovens. Conclusão: (I) A presença da trissomia 21 em crianças e adolescentes resultou em alterações bioquímicas que contribuem para o EO sistêmico e exacerbado nesses pacientes. (II) A terapia antioxidante com vitaminas E e C após 6 meses atenuou o EO. Adicionalmente, (III) o efeito da intervenção antioxidante persistiu significativamente após 6 meses de interrupção da suplementação. (IV). No estudo com camundongos TS também foi observado aumento do EO nos camundongos TS. A MEL foi capaz de diminuir o EO causado pela TS, especialmente nos animais adultos. Além disso, (V) o tratamento com a MEL não modificou a neurogênese nos animais jovens.Abstract : Down syndrome (DS), the most frequent genetic disorder, is almost entirely caused by trisomy of human chromosome 21. The overgeneration of reactive oxygen species (ROS) is involved in DS pathogenesis. The aim of this study was (I) to evaluate biomarkers of oxidative stress (OS) in the blood of DS children and adolescents before and after an antioxidant supplementation with vitamins E and C, as well as (II) the effect of administration of melatonin (MEL) on OS biomarkers and neurogenesis in an SD animal model (Ts65Dn mice). Biomarkers of OS and contents of inflammatory cytokines were evaluated in the blood of DS patients (n=21) before and after a daily antioxidant intervention (vitamin E 400 mg, vitamin C 500 mg) during 6 months followed by an interruption of the supplementation (also 6 months), followed by a new supplementation (6 months). Healthy children (n=18) without DS were recruited to constitute the control group. The activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione S-transferase (GST), gamma-glutamyltransferase (GGT), glucose-6-phosphate dehydrogenase (G6PD) and myeloperoxidase (MPO), as well as the contents of reduced glutathione (GSH), uric acid (UA), vitamin E, thiobarbituric acid reactive substances (TBARS), protein carbonyls (PC), transferrin, TNF-a and IL-1ß, were measured. Before the antioxidant therapy DS patients showed elevated SOD, CAT, GR, GGT and MPO activity and also elevated UA, transferrin, TNF-a and IL-1ß levels. The GST activity, GSH and PC levels were decreased, while GPx and G6PD activity and also plasma levels of vitamin E and TBARS showed no significant differences compared to controls. After the antioxidant supplementation, the activity of SOD, CAT, GPx, GR, GGT and MPO were downregulated, while TBARS contents were strongly decreased. No changes in G6PD and GST activities as well as in UA, PC, transferrin, TNF-a and IL-1ß levels were detected, while the contents of GSH and vitamin E were significantly increased. After interruption of the antioxidant therapy, DS patients showed elevated GPx and GGT activities as well as elevated UA and TBARS levels, while no changes in SOD, CAT, GR, GST, G6PD and MPO activities as well as in GSH, vitamin E, PC, transferrin, TNF-a and IL-1ß levels were detected. After the new period of supplementation there was an increase in plasma levels of vitamin E and decreased GGT activity, while nochanges in SOD, CAT, GPx, GR, G6PD, GST and MPO activity as well as in the contents of GSH, UA, transferrin, TBARS, PC, TNF-a and IL-1ß. The MEL intervention in young and adult animals used two groups of mice with different genotypes, controls (euploid littermates) and Ts65Dn (with trisomy), which were subdivided and treated with vehicle (water containing 0.06% ethanol) and/or MEL (100 mg/L), forming four groups: CO+Vehicle, CO+MEL, TS+Vehicle and TS+MEL. For young animals treatment occurred from the pre-natal stage with pregnant females and extended until the age of experiment (5.5 months), while for adults the treatment began and lasted 5.5 to 10.5 months of age. Both young and adults were assessed through OS biomarkers in the cortex and hippocampus. Neurogenesis of young animals (in adults data were already published) was assessed by immunohistochemistry for Ki-67 (nuclear protein expressed in cells in mitosis) and DAPI (nuclear marker) in the hippocampus. MEL administration decreased SOD and CAT activity while no changes in the activity of GPx and GR, as well as in levels of TBARS and PC in the cortex and hippocampus were detected. In adults MEL treatment promoted decreased SOD activity only in the cortex, as well as TBARS and PC levels in the hippocampus, whereas no changes in the CAT, GPx and GR activity in the cortex and hippocampus were detected. No changes in the density of Ki-67 and DAPI cells after treatment with MEL in young animals. Conclusions: (I) The presence of trisomy 21 in children and adolescents results in biochemical changes that strongly contributes to a systemic and exacerbated oxidative stress in these patients. (II) The antioxidant intervention with vitamins E and C for 6 months consistently attenuated such oxidative insult. Furthermore, (III) the effect of the antioxidant intervention persisted after 6 months of withdrawal of the antioxidant supplementation. (IV) In the study with TS mice, increased OS in brain was also observed. (V) MEL was able to decrease OS caused by TS, especially in adult animals, while it did not alter neurogenesis in young animals
