bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of an IQGAP1/AKAP79 complex in β‐cells
Authors: Nauert J. Brian , Rigas Johanna D. , Lester Linda B. 
Published: August 2003

AbstractIQGAP1, is a recently discovered scaffold protein proposed to regulate membrane cytoskeleton events through protein–protein interactions with F‐actin, E‐cadherin, β‐catenin, and CLIP170. The binding of IQGAP1 to its partners is regulated by calcium/calmodulin (Ca++/CaM) and the small molecular weight guanine nucleotide triphosphatases (GTPases), Cdc42, and Rac1. Here we identify a novel IQGAP1 scaffolding function by isolating the cyclic AMP dependent kinase (PKA) with IQGAP1. IQGAP1 was co‐purified with PKA using 5′‐cyclic AMP (cAMP) affinity chromatography and PKA activity was co‐immunoprecipitated with IQGAP1 using an anti‐IQGAP1 antibody. The association of IQGAP1 with PKA was shown to occur through a direct interaction between A kinase anchoring protein 79 (AKAP79) and the carboxyl‐terminal domain of IQGAP1. This suggests that cAMP/PKA may be coupled with Ca++/CaM and GTPases through an IQGAP1/AKAP79 complex. J. Cell. Biochem. 90: 97–108, 2003. © 2003 Wiley‐Liss, Inc.
Vitamin D and androgen regulation of prostatic growth
Authors: Leman Eddy S. , Arlotti Julie A. , Dhir Rajiv , Getzenberg Robert H. 
Published: August 2003

AbstractVitamin D has been reported to inhibit the growth of prostate cancer cells and model systems. In this study, we examined the interaction between 1,25‐dihydroxyvitamin D3 (1,25 D) in the presence or absence of endogenous testosterone on the growth and development of the adult rat prostate. Male Sprague–Dawley rats (165 days old) were either kept intact or castrated. Seven days after castration, the rats were treated with vehicle (control) or 1,25 D for 3 weeks and then sacrificed. Both ventral and dorsal lateral prostates were harvested; whole tissue lysates were collected and AR and VDR protein levels were analyzed by immunoblot analyses. Administration of 1,25 D in the intact animals decreased the prostatic size by 40%, compared to control animals, whereas 1,25 D did not influence the size of the prostate in castrated rats. 1,25 D administration in intact groups also increased both the AR and VDR protein levels by ∼twofold, whereas in castrated groups, 1,25 D only increased the AR protein level by 1.5–2.5‐fold. 1,25 D in the presence of endogenous testosterone inhibits prostatic growth, whereas 1,25 D in the absence of endogenous testosterone does not affect prostatic growth. The growth inhibitory activity of 1,25 D in the presence of testosterone may be mediated through the ligand activated AR and VDR pathways. These studies may reveal important information about the potential efficacy of 1,25 D as well as hormonal status in understanding the development of prostate diseases. J. Cell. Biochem. 90: 138–147, 2003. © 2003 Wiley‐Liss, Inc.
Estrogen regulates cytokine production and apoptosis in PMA‐differentiated, macrophage‐like U937 cells
Authors: Carruba Giuseppe , D'Agostino Pietro , Miele Monica , Calabrò Maurizio , Barbera Caterina , Bella Gloria Di , Milano Salvatore , Ferlazzo Viviana , Caruso Rosalba , Rosa Marzia La , Cocciadiferro Letizia , Campisi Ildegarda , Castagnetta Luigi , Cillari Enrico 
Published: August 2003

AbstractWe have investigated the effects of sex steroids, estradiol (E2), and testosterone (T) on the synthesis of tumor necrosis factor alpha (TNF‐α) and interleukin‐10 (IL‐10) in phorbol‐myristate‐acetate (PMA)‐differentiated human monoblastic U937 cells. The ability of both hormones to modulate the viability and programmed cell death of macrophage‐like PMA‐differentiated U937 cells was also inspected. E2 increased TNF‐α synthesis, whereas T had no effect on the production of this cytokine. The combination of E2 and its antagonist tamoxifen or ICI‐182,789 completely abolished the induction of TNF‐α, while combination of T and its antagonist Casodex (CSDX) did not significantly affect TNF‐α production by U937 cells. Exposure of cells to E2 resulted in a dose‐dependent decrease of IL‐10 synthesis, while again T did not show any detectable effect. In addition, E2 induced a significant increase of apoptosis in macrophage‐like U937 cells and this increase was inhibited by the simultaneous addition of either tamoxifen or ICI‐182. In contrast, T alone or in combination with CSDX did not modify apoptotic rates of U937 cells. This evidence, taken together, suggests that estrogens, but not androgens, exert a pro‐inflammatory action through the modulation of TNF‐α and IL‐10, and regulate the immune effector cells by the induction of programmed cell death. J. Cell. Biochem. 90: 187–196, 2003. © 2003 Wiley‐Liss, Inc.
Cyclic tensile stretch modulates proteoglycan production by intervertebral disc annulus fibrosus cells through production of nitrite oxide
Authors: Rannou François , Richette Pascal , Benallaoua Mourad , François Mathias , Genries Valérie , Korwin‐Zmijowska Carla , Revel Michel , Corvol Maité , Poiraudeau Serge 
Published: August 2003

AbstractDegeneration of the intervertebral disc is the main pathophysiological process implicated in low back pain and is a prerequisite to disc herniation. Clinically, mechanical forces are important modulators of the degeneration, but the underlying molecular mechanism is not known and needs investigation to identify the biological target. The aim of this work was to study, at the molecular level, the effects of cyclic tensile stretch (CTS) on the production of proteoglycan by intervertebral disc annulus fibrosus cells since proteoglycans seem to be implicated in the dynamic process of intervertebral disc degeneration. Such cells of rabbit were cultured at high density on plates with a flexible bottom. CTS was applied with use of a pressure‐operated instrument to deform the plates. With CTS at 1% elongation (1 Hz frequency), the level of 35S‐labeled neosynthesized proteoglycans that accumulated in the cellular pool or were secreted in the culture medium did not change, but at 5% elongation, the level was significantly reduced after 8 h of stimulation (30 and 21%, respectively) and further reduced at 24 h (43 and 41%, respectively). Introducing the protein synthesis inhibitor cycloheximide had no effect on this result. Neither aggrecan and biglycan expression nor proteoglycan physical properties were modified. The level of nitrite oxide production significantly increased by 3.5 times after 8 h of 5% elongation. Introducing the nitric oxide synthase (NOS) inhibitors NG‐methyl‐l‐arginine or N‐omega nitro‐l‐arginine diminished the effects of CTS on the production of nitrite oxide and proteoglycans. By contrast, introducing N‐iminoethyl‐l‐lysine (a more specific inhibitor of inductible NOS [iNOS]) had little or no effect. Taken together, these results suggest that cNOS activation seems to be more implicated in the 5% CTS modulation of proteoglycan production than iNOS activation. These results suggest that CTS can help regulate the intervertebral disc matrix by decreasing proteoglycan production through a post‐translational regulation involving nitrite oxide. This result could be of interest in the development of local therapeutic strategies aimed at controlling intervertebral disc degeneration. J. Cell. Biochem. 90: 148–157, 2003. © 2003 Wiley‐Liss, Inc.
Identification and characterization of a novel enhancer for the human MCT‐1 oncogene promoter
Authors: Shi Bo , Levenson Victor , Gartenhaus Ronald B. 
Published: August 2003

AbstractCloning and characterization of the promoter region for the MCT‐1 oncogene is described. We used luciferase assays to identify cis‐acting elements responsible for human MCT‐1 promoter function. The MCT‐1 promoter is TATA‐less with a consensus initiator element located at the transcription start site and facilitated by two Sp1 sites that directs basal transcription. Deletion of a region of the MCT‐1 promoter (−133 to −122) resulted in significant decrease in luciferase activity, suggesting that this region contains a positive cis‐acting element. Using mobility shift assays with a 26‐mer oligonucleotide, which contains this fragment and its flanking regions, we demonstrated the presence of sequence‐specific DNA‐binding protein in both Jurkat and Hela nuclear extracts that we designated as LMBF (for lymphoid MCT‐1 binding factor). This 26‐mer oligonucleotide containing the LMBF binding site is required for maximum transcriptional activity of the MCT‐1 promoter. Although the 26‐mer oligonucleotide contains a sequence with strong homology to a heat‐shock factor consensus, competitive electrophoretic mobility shift assay (EMSA) analysis demonstrated that the binding protein is not a known member of heat shock family. Furthermore, this sequence when placed in reverse orientation downstream of the luciferase gene was able to enhance luciferase activity driven by a minimal promoter. These data are consistent with this sequence behaving as an enhancer. Finally, Southwestern blot analysis revealed a 96‐kDa protein capable of binding a probe containing the LMBF binding site. J. Cell. Biochem. 90: 68–79, 2003. © 2003 Wiley‐Liss, Inc.
Effects of 18β‐Glycyrrhetinic acid on the junctional complex and steroidogenesis in rat adrenocortical cells
Authors: Huang Shih‐Horng , Wu Jiahn‐Chun , Hwang Ra‐Der , Yeo Hui‐Lin , Wang Seu‐Mei 
Published: August 2003

AbstractCellular junctions play important roles in cell differentiation, signal transduction, and cell function. This study investigated their function in steroid secretion by adrenal cells. Immunofluorescence staining revealed the presence of gap junctions and adherens junctions between adrenal cells. The major gap junction protein, connexin43, was seen as a linear dotted pattern of the typical gap junction plaques, in contrast to α‐, β‐, and γ‐catenin, which were seen as continuous, linear staining of cell–cell adherens junction. Treatment with 18β‐glycyrrhetinic acid, a gap junction inhibitor, reduced the immunoreactivity of these proteins in a time‐ and dose‐dependent manner, and caused the gap junction and adherens junction to separate longitudinally from the cell–cell contact sites, indicating the structural interdependency of these two junctions. Interestingly, 18β‐glycyrrhetinic acid stimulated a two‐ to three–fold increase in steroid production in these adrenal cells lacking intact cell junctions. These data raise the question of the necessity for cell communication for the endocrine function of adrenal cells. Pharmacological analyses indicated that the steroidogenic effect of 18β‐glycyrrhetinic acid was partially mediated by extracellular signal‐related kinase and calcium/calmodulin‐dependent kinase, a pathway distinct from the protein kinase A signaling pathway already known to mediate steroidogenesis in adrenal cells. J. Cell. Biochem. 90: 33–41, 2003. © 2003 Wiley‐Liss, Inc.
Regulation of nitric oxide and bcl‐2 expression by shear stress in human osteoarthritic chondrocytes in vitro
Authors: Lee Mel S. , Trindade Michael C.D. , Ikenoue Takashi , Goodman Stuart B. , Schurman David J. , Smith Robert Lane 
Published: August 2003

AbstractOnset and progression of cartilage degeneration is associated with shear stress occurring in diarthrodial joints subjected to inappropriate loading. This study tested the hypothesis that shear stress induced nitric oxide is associated with altered expression of regulatory onco‐proteins, bcl‐2, and Fas (APO‐1/CD95) and apoptosis in primary human osteoarthritic chondrocyte cultures. Shear stress induced membrane phosphatidylserine and nucleosomal degradation were taken as evidence of chondrocyte apoptosis. Application of shear stress upregulated nitric oxide in a dose‐dependent manner and was associated with increases in membrane phosphatidylserine and nucleosomal degradation. Increasing levels of shear stress decreased expression of the anti‐apoptotic factor, bcl‐2, from 44 to 10 U/ml. Addition of the nitric oxide antagonists, l‐N5‐(1‐iminoethyl) ornithine and Nω‐nitro‐l‐arginine methyl ester (L‐NAME), reduced shear stress induced nucleosomal degradation by 62% and 74%, respectively. Inhibition of shear stress induced nitric oxide release by l‐NAME coincided with a 2.7‐fold increase of bcl‐2, when compared to chondrocytes exposed to shear stress in the absence of l‐NAME. These data suggest that shear stress induced nitric oxide is associated with changes in apoptotic regulatory factors that alter chondrocyte metabolism and may contribute to joint degeneration. J. Cell. Biochem. 90: 80–86, 2003. © 2003 Wiley‐Liss, Inc.
TRPC3‐like protein is involved in the capacitative cation entry induced by 1α,25‐dihydroxy‐vitamin D3 in ROS 17/2.8 osteoblastic cells
Authors: Baldi Carolina , Vazquez Guillermo , Calvo Juan Carlos , Boland Ricardo 
Published: August 2003

AbstractIn ROS 17/2.8 rat osteoblastic‐like cells a capacitative Ca2+ entry (CCE) pathway operates which is activated by either 1α,25‐dihydroxy‐vitamin D3 (1α,25(OH)2D3) or thapsigargin (Tpg)‐induced depletion of Ca2+ stores (Baldi et al. [2002]: J. Cell. Biochem. 86:678–687). In view of recent evidence favoring a role for transient receptor potential (TRP) proteins in mediating CCE, we investigated if channels involved in the 1α,25(OH)2D3‐sensitive CCE in rat osteoblasts were related to an endogenous TRP‐canonical (TRPC) isoform homologue. By reverse transcription (RT)‐PCR using mRNA from ROS 17/2.8 cells and primers based on conserved regions within the mammalian TRPC3/6/7 subfamily, two fragments were amplified of 390 and 201 bp with 100 and 94% sequence identity, respectively, with human TRPC3. Northern blot analysis showed the presence of a 3.5 kb transcript and both immunobloting and immunocytochemistry using a specific anti‐TRPC3 antibody confirmed endogenous expression of a TRPC3‐like protein (∼110 kDa) with membrane localization. In ROS 17/2.8 cells intranuclearly microinjected with anti‐TRPC3 antisense oligodeoxynucleotides (ODN), both the initial rate and magnitude of CCE activated by either 1α,25(OH)2D3 or Tpg were markedly reduced, whereas no changes were detected in control‐injected cells. The present findings constitute the first evidence to date suggesting that an endogenous TRPC3‐like protein is functionally involved in the CCE route activated by 1α,25(OH)2D3 in a secosteroid target cell. We anticipate TRPC3 as a candidate for mediating store‐operated non‐selective cation entry into osteoblasts. J. Cell. Biochem. 90: 197–205, 2003. © 2003 Wiley‐Liss, Inc.
Activin A stimulates IκB‐α/NFκB and rank expression for osteoclast differentiation, but not AKT survival pathway in osteoclast precursors
Authors: Sugatani T. , Alvarez U.M. , Hruska K.A. 
Published: August 2003

AbstractRecent studies have reported that activin A enhances osteoclastogenesis in cultures of mouse bone marrow cells stimulated with receptor activator of nuclear factor‐κB ligand (RANKL) and macrophage colony‐stimulating factor (M‐CSF). However, the exact mechanisms by which activin A functions during osteoclastogenesis are not clear. RANKL stimulation of RANK/TRAF6 signaling increases nuclear factor‐κB (NFκB) nuclear translocation and activates the Akt/PKB cell survival pathway. Here we report that activin A alone activates IκB‐α, and stimulates nuclear translocation of NFκB and receptor activator of nuclear factor‐κB (RANK) expression for osteoclastogenesis, but not Akt/PKB survival signal transduction including BAD and mammalian target of rapamycin (mTOR) for survival in osteoclast precursors in vitro. Activin A alone failed to activate Akt, BAD, and mTOR by immunoblotting, and it also failed to prevent apoptosis in osteoclast precursors. While activin A activated IκB‐α and induced nuclear translocation of phosphorylated‐NFκB, and it also enhanced RANK expression in osteoclast precursors. Moreover, activin A enhanced RANKL‐ and M‐CSF‐stimulated nuclear translocation of NFκB. Our data suggest that activin A enhances osteoclastogenesis treated with RANKL and M‐CSF via stimulation of RANK, thereby increasing the RANKL stimulation. Activin A alone activated the NFκB pathway, but not survival in osteoclast precursors in vitro, but it is, thus, insufficient as a sole stimulus to osteoclastogenesis. J. Cell. Biochem. 90: 59–67, 2003. © 2003 Wiley‐Liss, Inc.
Differentiation potential of a mouse bone marrow stromal cell line
Authors: Allan Elizabeth H. , Ho Patricia W.M. , Umezawa Akihro , Hata Jun‐Ichi , Makishima Fusao , Gillespie Matthew T. , Martin T. John 
Published: August 2003

AbstractIn order to study osteoblast differentiation we subcloned a cell derived from a mouse a bone marrow stromal cell line, Kusa O, and obtained a number of clones representative of three different phenotypes. One that neither differentiated into osteoblasts nor into adipocytes, a second that differentiated into osteoblasts but not adipocytes, and a third that differentiated into both osteoblasts and adipocytes. Four subclones were selected for further characterization according to their ability to mineralize and/or differentiate into adipocytes. The non‐mineralizing clone had no detectable alkaline phosphatase activity although some alkaline phosphatase mRNA was detected after 21 days in osteoblast differentiating medium. Alkaline phosphatase activity and mRNA in the three mineralizing clones were comparable with the parent clones. Osteocalcin mRNA and protein levels in the non‐mineralizing clone were low and non‐detectable, respectively, while both were elevated in the parent cells and mineralizing subclones after 21 days in differentiating medium. PTH receptor mRNA and activity increased in the four subclones and parent cells with differentiation. mRNA for two other osteoblast phenotypic markers, osteopontin and bone sialoprotein, were similarly expressed in the parent cells and subclones while mRNAs for the transcription factors, Runx2 and osterix, were detectable in both parent and subclone cells. Runx2 was unchanged with differentiation while osterix was increased. Interestingly, PPARγ mRNA expression did not correlate with cell line potential to differentiate into adipocytes. Indian hedgehog mRNA and its receptor (patched) mRNA levels both increased with differentiation while mRNA levels of the Wnt pathway components β‐catenin and dickkopf also increased with differentiation. Although we have focussed on characterizing these clones from the osteoblast perspective it is clear that they may be useful for studying both osteoblast and adipocyte differentiation as well as their transdifferentiation. J. Cell. Biochem. 90: 158–169, 2003. © 2003 Wiley‐Liss, Inc.
Mitogen‐activated protein kinase pathway mediates DBP–maf‐induced apoptosis in RAW 264.7 macrophages
Authors: Gumireddy Kiranmai , Reddy C. Damodar , Swamy Narasimha 
Published: August 2003

AbstractVitamin D‐binding protein–macrophage‐activating factor (DBP–maf) is derived from serum vitamin D binding protein (DBP) by selective deglycosylation during inflammation. In the present study, we investigated the effect of DBP–maf on RAW 264.7 macrophages and the underlying intracellular signal transduction pathways. DBP–maf increased proapoptotic caspase‐3, ‐8, and ‐9 activities and induced apoptosis in RAW 264.7 cells. However, DBP, the precursor to DBP–maf did not induce apoptosis in these cells. Cell cycle analysis of DBP–maf‐treated RAW 264.7 cells revealed growth arrest with accumulation of cells in sub‐G0/G1 phase. We also investigated the role of mitogen‐activated protein kinase (MAPK) pathways in the DBP–maf‐induced apoptosis of RAW264.7 cells. DBP–maf increased the phosphorylation of p38 and JNK1/2, while it decreased the ERK1/2 phosphorylation. Treatment with the p38 MAPK inhibitor, SB202190, attenuated DBP–maf‐induced apoptosis. PD98059, a MEK specific inhibitor, did not show a significant inhibition of apoptosis induced by DBP–maf. Taken together, these results suggest that the p38 MAPK pathway plays a crucial role in DBP–maf‐mediated apoptosis of macrophages. Our studies indicate that, during inflammation DBP–maf may function positively by causing death of the macrophages when activated macrophages are no longer needed at the site of inflammation. In summary, we report for the first time that DBP–maf induces apoptosis in macrophages via p38 and JNK1/2 pathway. J. Cell. Biochem. 90: 87–96, 2003. © 2003 Wiley‐Liss, Inc.
Functional potential of P2P‐R: A role in the cell cycle and cell differentiation related to its interactions with proteins that bind to matrix associated regions of DNA?
Authors: Scott Robert E. , Giannakouros Thomas , Gao Sizhi , Peidis Philippos 
Published: August 2003

AbstractP2P‐R is the alternately spliced product of the P2P‐R/PACT gene in that P2P‐R lacks one exon encoding 34 amino acids. The 250 kDa P2P‐R protein is the predominate product expressed in multiple murine cell lines. It is a highly basic protein that contains multiple domains including an N‐terminal RING type zinc finger, a proline rich domain, an RS region, and a C‐terminal lysine‐rich domain. P2P‐R binds the p53 and the Rb1 tumor suppressors and is phosphorylated by the cdc2 and SRPK1a protein kinases. P2P‐R also interacts with scaffold attachment factor‐B (SAF‐B), a well characterized MARs (for matrix attachment regions) binding factor, and may interact with nucleolin, another MARs binding factor. In addition, P2P‐R binds single strand DNA (ssDNA). The expression of P2P‐R is regulated by differentiation and cell cycle events. P2P‐R mRNA is markedly repressed during differentiation, whereas immunoreactive P2P‐R protein levels are >10‐fold higher in mitotic than in G0 cells. The localization of P2P‐R also is modulated during the cell cycle. During interphase, P2P‐R is present primarily in nucleoli and nuclear speckles whereas during mitosis, P2P‐R associates with the periphery of chromosomes. Overexpression of near full length P2P‐R induces mitotic arrest in prometaphase and mitotic apoptosis, and overexpression of selected P2P‐R segments also can promote apoptosis. This compendium of data supports the possibility that P2P‐R may form complexes with the Rb1 and/or p53 tumor suppressors and MARs‐related factors, in a cell cycle and cell differentiation‐dependent manner, to influence gene transcription/expression and nuclear organization. J. Cell. Biochem. 90: 6–12, 2003. © 2003 Wiley‐Liss, Inc.
Network visualization system for computational chemistry
Authors: Kozhin Mikhail , Yanov Ilya , Leszczynski Jerzy 
Published: August 2003

AbstractNetwork Visualization System for Computational Chemistry (NVSCC) is a molecular graphics program designed for the visualization of molecular assemblies. NVSCC accepts the output files from the most popular ab initio quantum chemical programs, GAUSSIAN and GAMESS, and provides visualization of molecular structures based on atomic coordinates. The main differences between NVSCC and other programs are:

Network support due to built‐in FTP and telnet clients, which allows for the processing of output from and the sending of input to different computer systems and operating systems.

The possibility of working with output files in real time mode.

The possibility of animation from an output file during all steps of optimization.

The quick processing of huge volumes of data.

The development of custom interfaces.

© 2003 Wiley Periodicals, Inc. J Comput Chem 24: 1678–1688, 2003