bluuebunny/crossref_metadata_2025_split huggingface dataset:
Normal skin wound and hypertrophic scar myofibroblasts have differential responses to apoptotic inductors
Authors: Moulin Véronique , Larochelle Sébastien , Langlois Céline , Thibault Isabelle , Lopez‐Vallé Carlos A. , Roy Michel 
Published: January 2004

AbstractDuring wound healing, myofibroblasts play a central role in matrix formation and wound contraction. At the end of healing, there is evidence that myofibroblasts disappear via apoptotic pathways. Hypertrophic scars are a fibroproliferative disorder that leads to considerable morbidity. It has been postulated that a defect in myofibroblast apoptosis could be responsible for the pathological scar formation, but no evidence exists. We have isolated and cultured human normal wound (Wmyo) and hypertrophic scar (Hmyo) myofibroblasts and compared their basal apoptotic rates and their sensitivity to serum starvation and Fas antibody‐induced apoptosis to that obtained for dermal fibroblasts (Fb). A higher rate of apoptosis as evidenced by morphological criteria and a propidium iodide assay was observed for Wmyo in comparison to Fb and Hmyo. These results came along with a low level of the anti‐apoptotic proteins Bcl‐2 and BclxL in Wmyo, whereas there was an increase in the level of the pro‐apoptotic molecule Bax when compared to the results obtained for Fb and Hmyo. Hmyo showed a higher level of Bcl‐2 compared to Fb but no difference in the Bax or BclxL level. After serum starvation, Wmyo revealed an increased apoptotic rate, whereas Hmyo and Fb did not show any difference. Anti‐Fas treatment did not modify the levels of apoptosis but strongly increased the cell growth of Hmyo as compared to Wmyo. This is the first study presenting a broad vision of the apoptotic sensitivity of normal and pathological myofibroblasts. These results confirmed the hypothesis of defects in apoptosis and growth during pathological scar formation impeding myofibroblast disappearance at the end of healing. J. Cell. Physiol. 198: 350–358, 2004© 2003 Wiley‐Liss, Inc.
Simultaneous activation of several second messengers in hypoxia‐induced hyperpermeability of brain derived endothelial cells
Authors: Fischer Silvia , Wiesnet Marion , Marti Hugo H. , Renz Dieter , Schaper Wolfgang 
Published: January 2004

AbstractIn vivo, ischemia is known to damage the blood–brain barrier (BBB) leading to the development of vasogenic brain edema. Hypoxia‐induced vascular endothelial growth factor (VEGF) has been shown to be a key regulator of these permeability changes. However, the signaling pathways that underlie VEGF‐induced hyperpermeability are incompletely understood. In this study, we demonstrate that hypoxia‐ and VEGF‐induced permeability changes depend on activation of phospholipase Cγ (PLCγ), phosphatidylinositol 3‐kinase/Akt (PI3‐K/Akt), and protein kinase G (PKG). Inhibition of mitogen‐activated protein kinases (MAPK) and of the protein kinase C (PKC) did not affect permeability at all. Paralleling hypoxia‐ and VEGF‐induced permeability changes, localization of the tight junction proteins occludin, zonula occludens‐1 (ZO‐1), and ZO‐2 along the cell membrane changed from a continuous to a more discontinuous expression pattern during hypoxia. In particular, localization of ZO‐1 and ZO‐2 expression moved from the cell membrane to the cytoplasm and nucleus whereas occludin expression remained at the cell membrane. Inhibition of PLCγ, PI3‐kinase, and PKG abolished these hypoxia‐induced changes. These findings demonstrate that hypoxia and VEGF induce permeability through rearrangement of endothelial junctional proteins which involves activation of the PLCγ and PI3‐K/AKT pathway leading to the activation of PKG. J. Cell. Physiol. 198: 359–369, 2004© 2003 Wiley‐Liss, Inc.
Enterocytin: A new specific enterocyte marker bearing a B30.2‐like domain
Authors: Parnis Stéphane , Nicoletti Cendrine , Ollendorff Vincent , Massey‐Harroche Dominique 
Published: January 2004

AbstractEnterocyte differentiation is correlated to the expression of specific proteins which only a few of them are identified. In this study, we characterize a new marker of enterocyte differentiation using monoclonal antibodies. We showed that small intestinal enterocytes specifically express a new 47 kDa protein named Enterocytin. Expression of this protein increase along the crypt‐villus axis and it is concentrated in the terminal web, lateral plasma membrane domain, and nucleus membrane of mature enterocytes. A 1.8‐kb cDNA of Enterocytin was isolated by expression cloning from a cDNA library of rabbit small intestine. The amino acid sequence obtained shows an N‐terminal region with a coiled‐coil structure and a B30.2‐like domain in the C‐terminus region. By co‐transfection and immunoprecipitation procedures on Cos cells, it was observed that the coiled‐coil domain is involved in the homodimerization of Enterocytin. In the human intestine, a similar 47 kDa protein was detected, exclusively in the small intestinal enterocytes. In addition, expression of this protein in Caco2 cells is correlated with the state of differentiation of these cells. The restricted expression of Enterocytin in the intestine and its localization in mature cells suggest that it may contribute to the differentiation processes and maintenance of the enterocytic polarity. J. Cell. Physiol. 198: 441–451, 2004© 2003 Wiley‐Liss, Inc.
ERK1/2 and JNKs, but not p38 kinase, are involved in reactive oxygen species‐mediated induction of osteopontin gene expression by angiotensin II and interleukin‐1β in adult rat cardiac fibroblasts
Authors: Xie Zhonglin , Singh Mahipal , Singh Krishna 
Published: January 2004

AbstractOsteopontin (OPN), also called cytokine Eta‐1, expressed in the myocardium co‐incident with heart failure plays an important role in post myocardial infarction (MI) remodeling by promoting collagen synthesis and accumulation. Angiotensin II (Ang II) and inflammatory cytokines are increased in the heart following MI. We studied the involvement of mitogen‐activated protein kinases (ERK1/2, JNKs, p38 kinase) and reactive oxygen species (ROS) in Ang II‐ and cytokine‐induced OPN gene expression in adult rat cardiac fibroblasts. Ang II alone increased OPN mRNA (3.3 ± 0.3‐folds; P < 0.05; n = 7), while interleukin‐1β (IL‐1β), tumor necrosis factor (TNF‐α), and interferon‐γ (IFN‐γ) had no effect. A combination of Ang II with IL‐1β or TNF‐α, not IFN‐γ, increased OPN mRNA more than Ang II alone. Nitric oxide donor, S‐nitrosoacetylpenicillamine (SNAP), alone or in combination with Ang II had no effect. Diphenylene iodonium (DPI), inhibitor of NAD(P)H oxidase, and tiron, superoxide scavenger, inhibited Ang II‐ and Ang II+ IL‐1β‐stimulated increases in OPN mRNA. Ang II activated ERK1/2 within 5 min of treatment, not JNKs. IL‐1β activated ERK1/2 and JNKs within 15 min of treatment. A combination of Ang II and IL‐1β activated ERK1/2 within 5 min of treatment. None of these stimuli activated p38 kinase. DPI almost completely inhibited Ang II + IL‐1β‐stimulated activation of ERK1/2, while partially inhibiting JNKs. PD98059, ERK1/2 pathway inhibitor, and SP600125, JNKs inhibitor, partially inhibited Ang II + IL‐1β‐stimulated increases in OPN mRNA. A combination of PD98059 and SP600125 almost completely inhibited Ang II + IL‐1β‐stimulated increases in OPN mRNA. Thus, Ang II alone increases OPN expression, while IL‐1β and TNF‐α act synergistically with Ang II to increase OPN mRNA possibly via NO independent mechanisms. The synergistic increase in OPN mRNA involves ROS‐mediated activation of ERK1/2 and JNKs, not P38 kinase, pathways in cardiac fibroblasts. J. Cell. Physiol. 198: 399–407, 2004© 2003 Wiley‐Liss, Inc.
Differentiation of H9c2 cardiomyoblasts: The role of adenylate cyclase system
Authors: Pagano M. , Naviglio S. , Spina A. , Chiosi E. , Castoria G. , Romano M. , Sorrentino A. , Illiano F. , Illiano G. 
Published: January 2004

AbstractThe adenylate cyclase (AC)/cAMP/cAMP‐dependent protein kinase pathway controls many biological phenomena. The molecular mechanisms by which cAMP induces alternative commitment towards differentiation or proliferation are not still completely known. The differentiation of myoblast cell lines into myocytes/myotubes represents a well‐established model of skeletal muscle differentiation. We analyzed the AC/cAMP pathway during terminal differentiation of H9c2 myoblasts. When cultured in low‐serum containing medium, H9c2 myoblasts exit the cell cycle and differentiate into myocytes/myotubes. A key step of this process is the expression of myogenin, an essential transcription factor for the terminal differentiation into myocytes. During this phenomenon we observed a decrease in both cAMP levels and AC activity, which suggests a functional negative role of cAMP on the differentiation process of H9c2 cells. 8‐Br‐cAMP and other cAMP‐elevating agents, such as forskolin, IBMX, and isoproterenol, negatively affected skeletal muscle differentiation of H9c2 myoblasts. Both AC activity down‐regulation and intracellular cAMP reduction were accompanied by significant variations in the levels of membrane proteins belonging to the AC system (AC catalytic subunit, Gαi−1, Gαs). The functional relationship between intracellular cAMP content and protein levels of AC system is discussed. J. Cell. Physiol. 198: 408–416, 2004© 2003 Wiley‐Liss, Inc.
CREB Cooperates with BMP‐stimulated Smad signaling to enhance transcription of the Smad6 promoter
Authors: Ionescu Andreia M. , Drissi Hicham , Schwarz Edward M. , Kato Mitsuyasu , Puzas J. Edward , McCance Dennis J. , Rosier Randy N. , Zuscik Michael J. , O'Keefe Regis J. 
Published: January 2004

AbstractGrowth plate chondrocytes integrate a multitude of growth factor signals during maturation. PTHrP inhibits maturation through stimulation of PKA/CREB signaling while the bone morphogenetic proteins (BMPs) stimulate maturation through Smad mediated signaling. In this manuscript, we show that interactions between CREB and the BMP associated Smads are promoter specific, and demonstrate for the first time the requirement of CREB signaling for Smad mediated activation of a BMP responsive region of the Smad6 promoter. The 28 base pairs (bp) BMP responsive element of the Smad6 promoter contains an 11 bp Smad binding region and an adjacent 17 bp region in which we characterize a putative CRE site. PKA/CREB gain of function enhanced BMP stimulation of this reporter, while loss of CREB function diminished transcriptional activity. In contrast, ATF‐2 and AP‐1 transcription factors had minimal effects. Electrophoretic mobility shift assay (EMSA) confirmed CREB binding to the Smad6 promoter element. Mutations eliminating binding resulted in loss of transcriptional activity, while mutations that maintained CREB binding had continued reporter activation by CREB and BMP‐2. The Smad6 gene was similarly regulated by CREB. Dominant negative CREB reduced BMP‐2 stimulated Smad6 gene transcription by 50%, but markedly increased BMP‐2 mediated stimulation of colX and Ihh expression. In contrast, PTHrP which activates CREB signaling, blocked the stimulatory effect of BMP‐2 on colX and Ihh, but minimally inhibited the stimulatory effect of BMP on Smad6. These findings are the first to demonstrate a cooperative association between CREB and BMP regulated Smads in cells from vertebrates and demonstrate that promoter‐specific rather than generalized interactions between PKA/CREB and BMP signaling regulate gene expression in chondrocytes. J. Cell. Physiol. 198: 428–440, 2004© 2003 Wiley‐Liss, Inc.
Different roles of p38 MAPK and ERK in STI571‐induced multi‐lineage differentiation of K562 cells
Authors: Kohmura Kanoko , Miyakawa Yoshitaka , Kawai Yoko , Ikeda Yasuo , Kizaki Masahiro 
Published: January 2004

AbstractSTI571 is a specific tyrosine kinase inhibitor of Abl kinase. It was previously reported that STI571 induced hemoglobin synthesis in the chronic myelogenous leukemia (CML) cell line K562. However, its mechanisms remain unknown. In this study, we demonstrated that STI571 induced the phosphorylation of p38 mitogen‐activated protein kinase (MAPK) and dephosphorylation of extracellular signal‐regulated kinase (ERK) in K562 cells. In contrast, the phosphorylation of c‐Jun N‐terminal kinases (JNK) in K562 cells was not altered by STI571. We also found that STI571 induced all the myeloid (CD11b, CD13), megakaryocytic (CD41a, CD42), and erythroid (glycophorin‐A) markers on K562 cells. A p38 MAPK‐specific inhibitor, SB203580, inhibited the STI571‐induced multi‐lineage differentiation of K562 cells, indicating that p38 MAPK is crucial for this differentiation. In contrast, SB203580 did not overcome the inhibitory effect for proliferation of K562 cells, indicating that p38 MAPK activation by STI571 does not affect cell numbers. Among the hematopoietic transcription factors, the expression level of c‐myb mRNA was clearly downregulated after incubation with STI571 in K562 cells. STI571‐induced downregulation of c‐myb mRNA was prevented by the pretreatment of K562 cells by SB203580. Our data provides insights into how p38 MAPK and ERK pathways are involved in STI571‐induced differentiation of K562 cells. J. Cell. Physiol. 198: 370–376, 2004© 2003 Wiley‐Liss, Inc.
Recruitment and proliferation of T lymphocytes is supported by IFNγ‐ and TNFα‐activated human osteoblasts: Involvement of CD54 (ICAM‐1) and CD106 (VCAM‐1) adhesion molecules and CXCR3 chemokine receptor
Authors: Lisignoli Gina , Toneguzzi Stefania , Piacentini Anna , Cristino Sandra , Cattini Luca , Grassi Francesco , Facchini Andrea 
Published: January 2004

AbstractThe mechanism by which osteoblasts (OB) interact and modulate the phenotype and proliferation of T lymphocytes during inflammation is not well known. The effects of two regulatory cytokines, TNFα and IFNγ, on the expression of CD54 (ICAM‐1) and CD106 (VCAM‐1) adhesion molecules and the CXCR3 ligands (CXCL9, CXCL10, CXCL11), were assessed in a primary culture of human OB by real‐time PCR, flow cytometry, and immunohistochemistry. In addition, we functionally evaluated the recruitment and proliferation of T lymphocytes grown with resting or stimulated OB. According to the present data IFNγ, either alone or in combination with TNFα, significantly up‐regulates the expression of CD54 and CD106 and induces the expression and release of CXCL9, CXCL10, CXCL11 in OB. The supernatant of TNFα‐ and IFNγ‐activated OB induces the recruitment of T lymphocytes more significantly than stimulation by CXCR3 ligands. T lymphocyte proliferation is significantly enhanced by direct contact with TNFα‐ and IFNγ‐activated OB or by incubation with the supernatant of TNFα‐ and IFNγ‐activated OB. Blocking experiments with anti‐CD11a, anti‐CD49d, anti‐CXCR3, and Bordetella pertussis toxin demonstrate that adhesion molecules and the CXCR3 chemokine receptor play a key role in the proliferation of T lymphocytes. The present study demonstrates the involvement of adhesion molecules (CD11a and CD49d) and chemokine receptor (CXCR3) in the mechanism by which OB recruit, interact, and modulate T lymphocyte proliferation under inflammatory conditions. J. Cell. Physiol. 198: 388–398, 2004© 2003 Wiley‐Liss, Inc.
PDGF‐BB enhances α1β1 integrin‐mediated activation of the ERK/AP‐1 pathway involved in collagen matrix remodeling by rat mesangial cells
Authors: Kagami Shoji , Urushihara Maki , Kitamura Akiko , Kondo Shuji , Hisayama Tetsuhiro , Kitamura Masanori , Löster Klemens , Reutter Werner , Kuroda Yasuhiro 
Published: January 2004

AbstractPlatelet‐derived growth factor‐BB (PDGF‐BB) has been implicated in the pathogenesis of progressive glomerulonephritis (GN). Previous studies have reported that PDGF‐BB stimulates mesangial cells (MCs)‐induced collagen matrix remodeling through enhancement of α1β1 integrin‐dependent migratory activity. To determine the cell signaling pathway responsible for abnormal MC‐related mesangial matrix remodeling in progressive GN, we studied the involvement of the extracellular signal‐regulated kinase (ERK)/activator protein‐1 (AP‐1) pathway in PDGF‐BB‐enhanced collagen gel contraction. Western blotting and gel shift assay revealed that MC‐induced gel contraction resulted in ERK activation in parallel with that of AP‐1 binding, peaking at 4 h and lasting at least for 24 h. Application of the MEK inhibitor, U0126, and the c‐jun/AP‐1 inhibitor, curcumin, inhibited gel contraction and AP‐1 activity, respectively, dose dependently. PDGF‐BB enhanced not only gel contraction but ERK phosphorylation and AP‐1 activity by MCs. Marked inhibitory effects on PDGF‐BB‐induced gel contraction and ERK/AP‐1 activity were observed in the presence of either function blocking anti‐α1‐ or anti‐β1‐integrin antibody or U0126. Consistently, AP‐1‐inactive MCs expressing a dominant‐negative mutant of c‐jun showed a significant decrease of PDGF‐BB‐induced gel contraction as compared with mock‐transfected MCs. Finally, migration assay showed that ERK/AP‐1 activity is required for PDGF‐BB‐stimulated α1β1 integrin‐dependent MC migration to collagen I. These results indicated that PDGF‐BB enhances α1β1 integrin‐mediated collagen matrix reorganization through the activation of the ERK/AP‐1 pathway that is crucial for MC migration. We conclude that the ERK/AP‐1 pathway plays an important role in PDGF‐BB‐induced α1β1 integrin‐dependent collagen matrix remodeling; therefore, the inhibition of its pathway may provide a novel approach to regulate abnormal collagen matrix remodeling in progressive GN. J. Cell. Physiol. 198: 470–478, 2004© 2003 Wiley‐Liss, Inc.
ERK1/2 mediates TNF‐α‐induced matrix metalloproteinase‐9 expression in human vascular smooth muscle cells via the regulation of NF‐κB and AP‐1: Involvement of the ras dependent pathway
Authors: Moon Sung‐Kwon , Cha Byung‐Yoon , Kim Cheorl‐Ho 
Published: January 2004

AbstractThe expression of matrix metalloproteinase‐9 (MMP‐9) has been implicated in progression of atherosclerotic lesions. The role and importance of the signaling pathway in the transcriptional regulation of MMP‐9 in human aortic smooth muscle cells (HASMC) was examined. Tumor necrosis factor‐α (TNF‐α) stimulated the secretion of MMP‐9 in HASMC, as shown by zymography and immunoblot analysis. At the transcriptional levels, TNF‐α also stimulated the 5′‐flanking 710‐bp promoter activity of MMP‐9. Transcription factors NF‐κB binding site (−601) and AP‐1 binding site (−82) were identified as the cis‐elements for TNF‐α activation, as determined by gel shift assay and mutation analysis. Treatment with U0126, an inhibitor of the extracellular signal‐regulated kinase (ERK), significantly downregulated TNF‐α‐induced MMP‐9 expression and promoter activity, whereas the inactive analog U0124 had no effect. Furthermore, the transactivation of TNF‐α‐stimulated NF‐κB and AP‐1 was inhibited by U0126 treatment. Finally, the transient transfection of HASMC with dominant negative Ras (RasN17) suppressed TNF‐α‐induced ERK activity, MMP‐9 production, and promoter activity. Overexpression of RasN17 also abolished the TNF‐α‐stimulated NF‐κB and AP‐1 activity. In conclusion, the findings herein indicate the activation of the Ras/ERK pathway contributes to the induction of MMP‐9 expression in HASMC. In addition, the transcription factors NF‐κB and AP‐1 that are involved in the Ras/ERK‐mediated control of MMP‐9 regulation on HASMC in response to TNF‐α have now been identified. J. Cell. Physiol. 198: 417–427, 2004© 2003 Wiley‐Liss, Inc.
Induction of apoptosis by a hepatocyte conditioned medium
Authors: Bresgen Nikolaus , Rolinek R. , Hochleitner E. , Lottspeich F. , Eckl P.M. 
Published: January 2004

AbstractIncubation of primary cultures of parenchymal hepatocytes in a conditioned medium (CM), collected over the first 3 h of serum‐free rat hepatocyte culture (CM0–3), induces a time dependent increase of the frequency of apoptotic cells which is accompanied by prominent changes of cell morphology. Short‐term treatment with CM0–3 for the first 3 h of culture is sufficient to significantly (P < 0.05) increase the frequency of apoptotic cells, however, the effect is more pronounced upon long‐term treatment. Although apoptosis induction by CM0–3 is independent of the timepoint when cultivation in CM0–3 starts, our results suggest that the sensitivity for apoptosis induction by CM0–3 is increased during the phase of attachment. Purification of CM0–3 resulted in a fraction which significantly (P < 0.05) induced apoptosis at concentrations ≥10 ng/ml. Exposure of cultures to concentrations ≥1 μg/ml of purified CM0–3 gave rise to a prominent cytotoxic effect as indicated by the massive occurrence of necrotic cells. Biochemical analysis showed that the purified fraction of CM0–3 contains acidic ferritins with molecular weight of 23 and 43 kDa. Strikingly, both share homologies with placental isoferritins (PLF), for which growth inhibitory and immunosuppressive effects have been demonstrated by several investigations. Therefore, our results provide evidence that rat hepatocytes produce PLF or PLF‐related acidic isoferritins which are able to induce apoptosis. J. Cell. Physiol. 198: 452–460, 2004© 2003 Wiley‐Liss, Inc.
Kinase suppressor of RAS (KSR) amplifies the differentiation signal provided by low concentrations 1,25‐dihydroxyvitamin D3
Authors: Wang Xuening , Studzinski George P. 
Published: January 2004

AbstractThe activity of kinase suppressor of ras (KSR), a kinase or a molecular scaffold upstream from Raf‐1, is involved in the MEK/ERK MAP kinase cascade which can signal cell growth, survival, or differentiation, depending on the cellular context. We provide evidence here that KSR is upregulated in HL60 cells undergoing differentiation induced by low (0.3–3 nM) concentrations of 1,25‐dihydroxyvitamin D3 (1,25D3), and an antisense oligo (AS), but not a sense oligo, to KSR inhibits this differentiation. The inhibition of differentiation by AS–KSR oligo was less apparent when the concentration of 1,25D3 was increased, suggesting that at the higher concentrations of 1,25D3 KSR is not essential for the signaling of the differentiated phenotype. The reduced differentiation of HL60 cells exposed to AS–KSR was paralleled by reduced phosphorylation of Raf‐1 Ser 259, and of p90RSK, used here as read‐out for MAPK cascade activity. Conversely, ectopic expression of Flag‐tagged wild type KSR potentiated the differentiation‐inducing effects of low concentrations of 1,25D3. Additional data suggest that the kinase activity of KSR is required for these effects, as transfection of a kinase inactive KSR construct did not significantly increase the 1,25D3‐induced differentiation. Enzyme assays performed with KSR immunoprecipitated from 1,25D3‐treated cells showed kinase activity when recombinant Raf‐1 was used as the substrate, but not when the 1,25D3‐treated cells were pretreated with AS–KSR oligos. Taken together, these data suggest that KSR participates in signaling of monocytic differentiation by augmenting the strength of the signal transmitted through Raf‐1 to downstream targets. J. Cell. Physiol. 198: 333–342, 2004© 2003 Wiley‐Liss, Inc.