References of "Defresne, Marie-Paule"
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See detailCharacterization of spontaneous bone marrow recovery after sublethal total body irradiation: importance of the osteoblastic/adipocytic balance.
Poncin, Géraldine ULg; Beaulieu, Aurore ULg; Humblet, Chantal ULg et al

in PLoS ONE (2012), 7(2), 30818

Many studies have already examined the hematopoietic recovery after irradiation but paid with very little attention to the bone marrow microenvironment. Nonetheless previous studies in a murine model of ... [more ▼]

Many studies have already examined the hematopoietic recovery after irradiation but paid with very little attention to the bone marrow microenvironment. Nonetheless previous studies in a murine model of reversible radio-induced bone marrow aplasia have shown a significant increase in alkaline phosphatase activity (ALP) prior to hematopoietic regeneration. This increase in ALP activity was not due to cell proliferation but could be attributed to modifications of the properties of mesenchymal stem cells (MSC). We thus undertook a study to assess the kinetics of the evolution of MSC correlated to their hematopoietic supportive capacities in mice treated with sub lethal total body irradiation. In our study, colony-forming units - fibroblasts (CFU-Fs) assay showed a significant MSC rate increase in irradiated bone marrows. CFU-Fs colonies still possessed differentiation capacities of MSC but colonies from mice sacrificed 3 days after irradiation displayed high rates of ALP activity and a transient increase in osteoblastic markers expression while ppargamma and neuropilin-1 decreased. Hematopoietic supportive capacities of CFU-Fs were also modified: as compared to controls, irradiated CFU-Fs significantly increased the proliferation rate of hematopoietic precursors and accelerated the differentiation toward the granulocytic lineage. Our data provide the first evidence of the key role exerted by the balance between osteoblasts and adipocytes in spontaneous bone marrow regeneration. First, (pre)osteoblast differentiation from MSC stimulated hematopoietic precursor's proliferation and granulopoietic regeneration. Then, in a second time (pre)osteoblasts progressively disappeared in favour of adipocytic cells which down regulated the proliferation and granulocytic differentiation and then contributed to a return to pre-irradiation conditions. [less ▲]

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See detailLeptin Reverts Pro-Apoptotic and Antiproliferative Effects of α-Linolenic Acids in BCR-ABL Positive Leukemic Cells: Involvement of PI3K Pathway
Beaulieu, Aurore ULg; Poncin, Géraldine ULg; Belaid-Choucair, Zakia et al

in PLoS ONE (2011), 6(10), 25651

It is suspected that bone marrow (BM) microenvironmental factors may influence the evolution of chronic myeloid leukaemia (CML). In this study, we postulated that adipocytes and lipids could be involved ... [more ▼]

It is suspected that bone marrow (BM) microenvironmental factors may influence the evolution of chronic myeloid leukaemia (CML). In this study, we postulated that adipocytes and lipids could be involved in the progression of CML. To test this hypothesis, adipocytes were co-cultured with two BCR-ABL positive cell lines (PCMDS and K562). T cell (Jurkat) and stroma cell (HS-5) lines were used as controls. In the second set of experiments, leukemic cell lines were treated with stearic, oleic, linoleic or α-linolenic acids in presence or absence of leptin. Survival, proliferation, leptin production, OB-R isoforms (OB-Ra and OB-Rb), phosphoinositide 3-kinase (PI3k) and BCL-2 expression have been tested after 24h, 48h and 72h of treatment. Our results showed that adipocytes induced a decrease of CML proliferation and an increase in lipid accumulation in leukemic cells. In addition, CML cell lines induced adipocytes cell death. Chromatography analysis showed that BM microenvironment cells were full of saturated (SFA) and monounsaturated (MUFA) fatty acids, fatty acids that protect tumor cells against external agents. Stearic acid increased Bcl-2 expression in PCMDS, whereas oleic and linoleic acids had no effects. In contrast, α-linolenic acid decreased the proliferation and the survival of CML cell lines as well as BCL-2 and OB-R expression. The effect of α-linolenic acids seemed to be due to PI3K pathway and Bcl-2 inhibition. Leptin production was detected in the co-culture medium. In the presence of leptin, the effect of α-linolenic acid on proliferation, survival, OB-R and BCl-2 expression was reduced.</p> [less ▲]

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See detailH4 Histamine Receptors Mediate Cell Cycle Arrest in Growth Factor-Induced Murine and Human Hematopoietic Progenitor Cells
Petit-Bertron, Anne France; Machavoine, François; Defresne, Marie-Paule ULg et al

in PLoS ONE (2009), 4(8), 1-13

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See detailHuman bone marrow adipocytes block granulopoiesis through neuropilin-1-induced granulocyte colony-stimulating factor inhibition.
Belaid-Choucair, Zakia ULg; Lepelletier, Yves; Poncin, Géraldine ULg et al

in Stem Cells (2008), 26(6), 1556-64

Adipocytes are part of hematopoietic microenvironment, even though up to now in humans, their role in hematopoiesis is still questioned. We have previously shown that accumulation of fat cells in femoral ... [more ▼]

Adipocytes are part of hematopoietic microenvironment, even though up to now in humans, their role in hematopoiesis is still questioned. We have previously shown that accumulation of fat cells in femoral bone marrow (BM) coincides with increased expression of neuropilin-1 (NP-1), while it is weakly expressed in hematopoietic iliac crest BM. Starting from this observation, we postulated that adipocytes might exert a negative effect on hematopoiesis mediated through NP-1. To test this hypothesis, we set up BM adipocytes differentiated into fibroblast-like fat cells (FLFC), which share the major characteristics of primitive unilocular fat cells, as an experimental model. As expected, FLFCs constitutively produced macrophage colony stimulating factor and induced CD34(+) differentiation into macrophages independently of cell-to-cell contact. By contrast, granulopoiesis was hampered by cell-to-cell contact but could be restored in transwell culture conditions, together with granulocyte colony stimulating factor production. Both functions were also recovered when FLFCs cultured in contact with CD34(+) cells were treated with an antibody neutralizing NP-1, which proved its critical implication in contact inhibition. An inflammatory cytokine such as interleukin-1 beta or dexamethasone modulates FLFC properties to restore granulopoiesis. Our data provide the first evidence that primary adipocytes exert regulatory functions during hematopoiesis that might be implicated in some pathological processes. Disclosure of potential conflicts of interest is found at the end of this article. [less ▲]

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See detailNeighboring adipocytes participate in the bone marrow microenvironment of multiple myeloma cells
CAERS, Jo ULg; Deleu, Sara; Belaid, Zakia et al

in Leukemia : Official Journal of the Leukemia Society of America, Leukemia Research Fund, U.K (2007), 21(7), 1580-4

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See detailNeighboring adipocytes participate in the bone marrow microenvironment of multiple myeloma cells
Caers, Jo; Deleu, S.; Belaid, Zakia ULg et al

in Leukemia (2007), 21(7), 1580-1584

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See detailTumoral and choroidal vascularization: differential cellular mechanisms involving plasminogen activator inhibitor type I.
Jost, Maud; Maillard, Catherine ULg; Lecomte, Julie ULg et al

in American Journal of Pathology (2007), 171(4), 1369-80

An adequate balance between serine proteases and their plasminogen activator inhibitor-1 (PAI-1) is critical for pathological angiogenesis. PAI-1 deficiency in mice is associated with impaired choroidal ... [more ▼]

An adequate balance between serine proteases and their plasminogen activator inhibitor-1 (PAI-1) is critical for pathological angiogenesis. PAI-1 deficiency in mice is associated with impaired choroidal neovascularization (CNV) and tumoral angiogenesis. In the present work, we demonstrate unexpected differences in the contribution of bone marrow (BM)-derived cells in these two processes regulated by PAI-1. PAI-1(-/-) mice grafted with BM-derived from wild-type mice were able to support laser-induced CNV formation but not skin carcinoma vascularization. Engraftment of irradiated wild-type mice with PAI-1(-/-) BM prevented CNV formation, demonstrating the crucial role of PAI-1 delivered by BM-derived cells. In contrast, the transient infiltration of tumor transplants by local PAI-1-producing host cells rather than by BM cells was sufficient to rescue tumor growth and angiogenesis in PAI-1-deficient mice. These data identify PAI-1 as a molecular determinant of a local permissive soil for tumor angiogenesis. Altogether, the present study demonstrates that different cellular mechanisms contribute to PAI-1-regulated tumoral and CNV. PAI-1 contributes to BM-dependent choroidal vascularization and to BM-independent tumor growth and angiogenesis. [less ▲]

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See detailPlasminogen activator inhibitor type I (PAI-1) controls bone marrow-dependent and independent vascularization
Jost, M.; Maillard, Catherine ULg; Lambert, Vincent ULg et al

in Acta Clinica Belgica (2006), 61(2, MAR-APR), 87

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See detailMurine bone marrow stromal cells sustain in vivo the survival of hematopoietic stem cells and the granulopoietic differentiation of more mature progenitors.
Hubin, Frederique; Humblet, Chantal ULg; Belaid, Zakia ULg et al

in Stem Cells (2005), 23(10), 1626-33

The study of the human hematopoietic system would be facilitated by availability of a relevant animal model. Because the medullar microenvironment is made of different types of cells, interactions between ... [more ▼]

The study of the human hematopoietic system would be facilitated by availability of a relevant animal model. Because the medullar microenvironment is made of different types of cells, interactions between hematopoietic cells and stromal cells are difficult to analyze in detail. As an approach for establishing an in vivo model to dissect these interactions, we grafted murine bone marrow fibroblastic cells (MS-5 cell line) with hematopoietic cells into the kidney capsule of syngenic mice. To identify the origin of cells present in the graft, we used green fluorescent protein-stable transfected MS-5 cells for the transplantation. To analyze the evolution of stromal cells and identify hematopoietic cells able to develop in these conditions, we performed morphology, histochemistry, and immunohistology on tissue sections at different times after transplantation. When injected alone, MS-5 cells differentiate into adipocytes. When injected with a bone marrow suspension or with isolated CD45+ cells (leukocytes), the stromal cells keep their fibroblastic morphology and their alkaline phosphatase expression and sustain granulopoiesis. When injected with hematopoietic stem cells called c-kit+ Sca-1+ Lin- suspension, clusters of hematopoietic cells are also observed: They do not present any granulopoietic activity and do not belong to B or T population nor to erythroid lineage. They are quiescent, induce bone marrow recovery and survival of lethally irradiated recipients, are able to form macroscopic colonies in the spleen, and are able to form very few colonies in vitro, suggesting that they are hematopoietic stem cells. In conclusion, our results show that reticular fibroblastic stromal cells MS-5 sustain the survival of stem cells and are not able to induce their differentiation. However, they can control differentiation, proliferation, and/or survival of hematopoietic cells engaged in myeloid lineage. [less ▲]

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See detailDifferential expression of vascular endothelial growth factor and its receptors in hematopoietic and fatty bone marrow: evidence that neuropilin-1 is produced by fat cells.
Belaid, Zakia ULg; Hubint, Frederique; Humblet, Chantal ULg et al

in Haematologica (2005), 90(3), 400-1

Vascular endothelial growth factor (VEGF), its receptors (VEGFR-1, VEGFR-2) and neuropillin-1 (NRP-1) are expressed at variable levels in bone marrow. NRP-1expression is higher in fatty bone marrow than ... [more ▼]

Vascular endothelial growth factor (VEGF), its receptors (VEGFR-1, VEGFR-2) and neuropillin-1 (NRP-1) are expressed at variable levels in bone marrow. NRP-1expression is higher in fatty bone marrow than in hematopoietic marrow. Adipocytes are responsible for NRP-1 expression suggesting that they may play a role in hematopoiesis by producing NRP-1 or that NRP-1 may regulate adipocyte activity. [less ▲]

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See detailNeurohypophysial Receptor Gene Expression by Thymic T Cell Subsets and Thymic T Cell Lymphoma Cell Lines
Hansenne, Isabelle ULg; Rasier, G.; Charlet-Renard, C. et al

in Clinical & Developmental Immunology (2004), 11(1), 45-51

Neurohypophysial oxytocin (OT) and vasopressin (VP) genes are transcribed in thymic epithelium, while immature T lymphocytes express functional neurohypophysial receptors. Neurohypophysial receptors ... [more ▼]

Neurohypophysial oxytocin (OT) and vasopressin (VP) genes are transcribed in thymic epithelium, while immature T lymphocytes express functional neurohypophysial receptors. Neurohypophysial receptors belong to the G protein-linked seven-transmembrane receptor superfamily and are encoded by four distinct genes, OTR, V1R, V2R and V3R. The objective of this study was to identify the nature of neurohypophysial receptor in thymic T cell subsets purified by immunomagnetic selection, as well as in murine thymic lymphoma cell lines RL12-NP and BW5147. OTR is transcribed in all thymic T cell subsets and T cell lines, while V3R transcription is restricted to CD4+CD8+ and CD8+ thymic cells. Neither V1R nor V2R transcripts are detected in any kind of T cells. The OTR protein was identified by immunocytochemistry on thymocytes freshly isolated from C57BL/6 mice. In murine fetal thymic organ cultures, a specific OTR antagonist does not modify the percentage of T cell subsets, but increases late T cell apoptosis further evidencing the involvement of OT/OTR signaling in the control of T cell proliferation and survival. According to these data, OTR and V3R are differentially expressed during T cell ontogeny. Moreover, the restriction of OTR transcription to T cell lines derived from thymic lymphomas may be important in the context of T cell leukemia pathogenesis and treatment. [less ▲]

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See detailMaintenance of functional human cancellous bone and human hematopoiesis in NOD/SCID mice
Hubin, F.; Humblet, Chantal ULg; Belaid, Zakia ULg et al

in Cell Transplantation (2004), 13(7-8), 823-831

Attempts were made to establish models to study interactions between marrow stromal cells and hematopoietic cells in vivo. The approach was to create a NOD-SCID-hu murine model of long-term human ... [more ▼]

Attempts were made to establish models to study interactions between marrow stromal cells and hematopoietic cells in vivo. The approach was to create a NOD-SCID-hu murine model of long-term human hematopoiesis by implantation of a human adult bone fragment. Nine to 12 weeks posuransplantation, human CD45(+) cells were detected in the blood and the spleen of some mice. The histology of the human transplant showed that human bone fragment was viable at 9 weeks. Moreover, vessels of human origin, as assessed by immunohistochemical detection of human beta(2)-microglobulin, were observed in the mouse tissue surrounding the transplanted human fragment. [less ▲]

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See detailMarrow stromal cell recovery after radiation-induced aplasia in mice
Almohamad, Khaled; Thiry, Albert ULg; Hubin, Frédérique et al

in International Journal of Radiation Biology (2003), 79(4), 259-67

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See detailCyclosporin-A differentially affects apoptosis during in vivo rat thymocyte maturation
Damoiseaux, JGMC; Defresne, Marie-Paule ULg; Reutelingsperger, C. P. M. et al

in Scandinavian Journal of Immunology (2002), 56(4), 353-360

Maturation arrest and interference with selection are two well-documented effects of cyclosporin-A (CsA) on the thymus. We recently hypothesized that these effects are related and owing to the reduced T ... [more ▼]

Maturation arrest and interference with selection are two well-documented effects of cyclosporin-A (CsA) on the thymus. We recently hypothesized that these effects are related and owing to the reduced T-cell receptor (TCR)-CD3 complex-mediated signal transduction in thymocytes upon CsA treatment. In this hypothesis, the maturation arrest is the result of the additional depletion of thymocytes that normally survive by positive selection, whereas the impaired self-tolerance induction is caused by an increased survival of thymocytes that normally undergo negative selection. In this view, it is anticipated that CsA differentially affects thymocyte apoptosis during in vivo thymocyte maturation. Indeed, we report in this study a strong increase in apoptotic cells in the thymic cortex on in situ analysis. Simultaneously, the number of apoptotic cells had decreased at the cortico-medullary zone which is held to be the site for negative selection. Rapamycin (Rapa) also interferes with thymocyted maturation by inhibiting cytokine-driven proliferation. Hence, Rapa preferentially affects the early maturational stages of thymoctye development and is considered not to alter thymocyte selection and subsequent apoptotic events. Indeed, the number of apoptotic events appears not to be altered. However, possibly owing to the decrease in cortical macrophages, the apoptotic cells revealed an atypical enumeration around blood vessels. Taken together, our results favour the hypothesis that the dominant effect of CsA on the thymus is the reduction of the TCR-CD3 complex-mediated signal transduction in thymocytes upon interaction with stromal cells. Furthermore, the preferential localization of apoptotic cells next to blood vessels upon Rapa administration may indicate that endothelial cells are a back-up system for the removal of apoptotic cells. [less ▲]

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See detailTransient modifications of respiratory capacity in thymic cells during murine radioleukemogenesis
Verlaet, Myriam ULg; Duyckaerts, Claire ULg; Rahmouni, Souad ULg et al

in Free Radical Biology & Medicine (2002), 33(1), 76-82

The evolution of mitochondrial oxidative phosphorylation was studied during cancer induction in a model of thymic radiolymphomagenesis in C57BL/Ka mice. During the preneoplastic period, thymuses displayed ... [more ▼]

The evolution of mitochondrial oxidative phosphorylation was studied during cancer induction in a model of thymic radiolymphomagenesis in C57BL/Ka mice. During the preneoplastic period, thymuses displayed an increase of the cytochrome c oxidase activity and oxygen consumption together with oxidative DNA damage assessed by the presence of the 8-hydroxydeoxyguanine DNA base modification. These transient changes in mitochondrial functional activity were not observed in thymuses of mice rescued from lymphoma development by a bone marrow graft, suggesting an important role of mitochondria for neoplastic transformation in this model. which might therefore be of interest to test the utilization of antioxidants for the prevention of radiation-induced malignancies. (C) 2002 Elsevier Science Inc. [less ▲]

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See detailMetabolism of human articular chondrocytes cultured in alginate beads. Longterm effects of interleukin 1 beta and nonsteroidal antiinflammatory drugs
Sanchez, Christelle ULg; Mateus, Marguarita; Defresne, Marie-Paule ULg et al

in Journal of Rheumatology (2002), 29(4), 772-782

OBJECTIVES: To investigate the longterm effects (12 days) of nonsteroidal antiinflammatory drugs [NSAID: aceclofenac (ACECLO), sodium diclofenac (DICLO), indomethacin (INDO), nimesulide (NIM), rofecoxib ... [more ▼]

OBJECTIVES: To investigate the longterm effects (12 days) of nonsteroidal antiinflammatory drugs [NSAID: aceclofenac (ACECLO), sodium diclofenac (DICLO), indomethacin (INDO), nimesulide (NIM), rofecoxib (ROFE), celecoxib (CELE), piroxicam (PIROX), and ibuprofen (IBUP)] on the metabolism of human chondrocytes cultured in alginate beads. METHODS: Enzymatically isolated osteoarthritic (OA) chondrocytes were cultured in alginate beads in a well defined culture medium for 12 days. The DNA content was measured according to a fluorimetric method and cell proliferation was determined by the incorporation of 3H-thymidine in the newly synthesized DNA. Interleukin 6 (IL-6) and IL-8, stromelysin [matrix metalloproteinase-3 (MMP-3)], and aggrecan (AGG) production were assayed by specific enzyme amplified sensitivity immunoassays, and prostaglandin E2 (PGE2) production by specific radioimmunoassay. All NSAID were tested at the mean peak plasma concentration (Cmax) obtained after oral administration of a therapeutic dose. RESULTS: In alginate beads, chondrocytes synthesized high amounts of AGG, which were largely (98%) immobilized in the alginate matrix. A large amount (43%) of the IL-8 produced was stored in the alginate beads, whereas almost all IL-6 production (94%) was released in the culture supernatant. At the therapeutic concentration, all NSAID tested fully blocked PGE2 production. ACECLO, DICLO, INDO, NIM significantly inhibited basal and IL-1beta stimulated IL-6 production; CELE and IBUP only inhibited IL-1beta stimulated IL-6 production; and ROFE and PIROX had no significant effects. No NSAID showed significant effects on basal and IL-1beta stimulated IL-8 production, except CELE and IBUP, which slightly increased basal IL-8 production. ACECLO and INDO increased AGG content by 25% in the alginate beads, while the other NSAID were without significant effect. No NSAID were able to modify the inhibitory effect of IL-1beta on AGG production. NSAID did not modify MMP-3 production. CONCLUSION: The mechanism of action of NSAID seems to be multifactorial and not limited to the inhibition of cyclooxygenases. Further, in our culture conditions, at the Cmax and by comparison with other NSAID, ACECLO and INDO show an advantageous activity profile. They fully blocked PGE2 production, inhibited IL-6 synthesis, and increased aggrecan synthesis. These effects appear advantageous for the longterm treatment of chronic joint diseases such as osteoarthritis. [less ▲]

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See detailAssociation of a new c-Cbl related protein with the very first stages of apoptosis induction
Corsois, L.; Quatannens, B.; Dumont, P. et al

in Cancer Detection and Prevention (2002), 26(2), 93-104

This study investigates the involvement of the c-cbl proto-oncogene during the first stages of the apoptotic process. We have already shown that a c-Cbl aptotosis-related protein of 90 kDa (CARP 90) is ... [more ▼]

This study investigates the involvement of the c-cbl proto-oncogene during the first stages of the apoptotic process. We have already shown that a c-Cbl aptotosis-related protein of 90 kDa (CARP 90) is detected very rapidly in the cytoplasm as well as in the nucleus of murine thymocytes after hydrocortisone (HC) treatment. We report here that this protein appeared as well after in vivo treatment of mice by gamma-irradiation or injection of anti-CD3 monoclonal antibody, two potent thymic apoptosis inductors, providing a close relationship between the occurrence of apoptosis and the appearance of CARP 90. We showed that CARP 90 and p120(cbl) share numerous epitopes strikingly suggesting that CARP 90 is coded by c-cbl. In addition, KO mice do not sustain CARP 90 appearance. We finally showed that CARP 90 contains N- and C-terminal end epitopes of p120(cbl) which suggests that CARP 90 is an alternative spliced form of c-cbl. This protein was also observed under gamma-irradiation in tissues of different origin, which enlarges the physiological significance of this phenomenon. The very rapid CARP 90 appearance under apoptotic conditions in the nucleus of cells originating in different tissues makes this protein if not a possible new actor of the apoptotic process, at least an interesting marker of this process. (C) 2002 International Society for Preventive Oncology. Published by Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailAlkaline phosphatase positive reticular cell network recovery after radiation-induced marrow aplasia in mice
Almohamad, K.; Thiry, Anne-Marie ULg; Boniver, Jacques ULg et al

in Blood (2001, November 16), 98(11, Part 2), 141

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See detailSpermine-Induced Alteration of Small Intestine in Suckling Rat: Involvement of Apoptosis or Zn2+ Enzymes?
Peulen, Olivier ULg; Denis, Ghislaine; Defresne, Marie-Paule ULg et al

in Digestive Diseases & Sciences (2001), 46(11), 2490-8

Polyamines are of great importance in several physiological processes, such as cell proliferation and differentiation. The ingestion of spermine by suckling rats induces precocious maturation of their ... [more ▼]

Polyamines are of great importance in several physiological processes, such as cell proliferation and differentiation. The ingestion of spermine by suckling rats induces precocious maturation of their small intestine. Shortly after ingestion, spermine produces cell elimination at the villous top. The origin of this exfoliation was investigated to determine whether it was due to apoptosis. Wistar rats were orally treated with spermine. Apoptosis was analyzed in their small intestine by Tdt-mediated dUTP-fluorescein nick-end labeling reaction, caspase-3-like analysis, and DNA laddering. Polyamine content was measured by HPLC. The intestinal transitory alteration appeared as soon as 2 hr after spermine administration. Apoptosis events increased strongly at the same moment in the small intestine. They were evidenced by Tdt-mediated dUTP-fluorescein nick-end labeling analysis, DNA laddering, and caspase-3-like activity. Changes observed are consistent with apoptosis, but caspase inhibitor did not reduce intestinal alteration, as did Zn2+ chelator. [less ▲]

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See detailGenetic Imbalances in Preleukemic Thymuses
Verlaet, Myriam ULg; Deregowski, Valérie; Denis, Ghislaine et al

in Biochemical and Biophysical Research Communications (2001), 283(1), 12-8

To understand the molecular mechanisms involved in preleukemia, the suppression subtractive hybridization method was used in a murine radiation-induced thymic lymphoma model. Seventeen mRNAs overexpressed ... [more ▼]

To understand the molecular mechanisms involved in preleukemia, the suppression subtractive hybridization method was used in a murine radiation-induced thymic lymphoma model. Seventeen mRNAs overexpressed in preleukemic thymuses were identified: mouse laminin binding protein (p40/37LBP), E25 protein, Rattus norvegicus clone BB.1.4.1, profilin, poly(A) binding protein (PABP), mouse high mobility group protein 1, topoisomerase I, clusterin, proteasome RC1 subunit, rat prostatein C3 and C1 subunits; two ESTs and four unknown genes. The overexpression of PABP, clusterin, profilin, and the p40/37LBP mRNAs was confirmed in preleukemic thymuses and can be related to some cellular events observed during the preleukemic period, i.e., alterations of cell cycle and apoptosis properties. The p40/37LBP and 67-kDa laminin receptor proteins were upregulated during the preleukemic period. The data suggest that additional studies on p40/37LBP and 67-kDa laminin receptor regulation are required to evaluate their potential role in the lymphoma prevention by TNF-alpha and IFN-gamma. [less ▲]

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