bluuebunny/crossref_metadata_2025 huggingface dataset:
Restoration of TRAIL‐Induced Apoptosis in a Caspase‐8‐Deficient Neuroblastoma Cell Line by Stable Re‐expression of Caspase‐8
Authors: MÜHLETHALER‐MOTTET ANNICK , BALMAS KATIA , AUDERSET KATYA , JOSEPH JEAN‐MARC , GROSS NICOLE
Published: March 2004

Abstract: Tumor necrosis factor‐related apoptosis‐inducing ligand (TRAIL) selectively induces apoptosis in most tumor cells, a process sometimes potentiated by chemotherapeutic drugs or cycloheximide (CHX). Childhood neuroblastoma (NB) is a clinically and biologically heterogeneous neoplasm whose behavior can be explained by differential regulation of apoptosis. The non‐invasive S‐type NB cell lines are sensitive to TRAIL, whereas the invasive N‐type NB cell lines are resistant. We have reported the silencing of caspase‐8 expression in N‐type cells as a possible mechanism of death receptor‐mediated resistance to apoptosis in NB. The recently observed deregulation of caspase‐10 in these cells prompted us to investigate the particular contribution of caspase‐8 silencing in the resistance to TRAIL in N‐type cells. Stable caspase‐8 expression was therefore restored in the IGR‐N91 cell line by retroviral infection. The IGR‐N91‐C8 cells became sensitive to TRAIL‐mediated apoptosis, whereas the control vector‐infected IGR‐N91‐M cells remained resistant. Interestingly, the apoptotic response to TRAIL was enhanced by co‐treatment of SH‐EP and IGR‐N91‐C8 cells with CHX or with sub‐toxic concentration of doxorubicin (DOX) in a caspase‐dependent manner, as cells could be protected from death by specific caspase‐8 or pan‐caspase inhibitors. CHX or DOX was shown to enhance TRAIL‐induced caspase‐8 activation and loss of mitochondrial transmembrane potential. In conclusion, restoration of active caspase‐8 expression in caspase‐8‐ and caspase‐10‐deficient IGR‐N‐91 cell line is necessary and sufficient to fully restore TRAIL‐mediated cell death. Moreover, DOX and CHX were able to sensitize NB cell lines to TRAIL‐induced apoptosis in a caspase‐8‐dependent manner by engaging death receptor and mitochondrial signaling pathways.
Accumulation of Histones in Cell Lysates Precedes Expression of Apoptosis‐Related Phagocytosis Signals in Human Lymphoblasts
Authors: GABLER CHRISTOPH , BLANK NORBERT , WINKLER SILKE , KALDEN JOACHIM R. , LORENZ HANNS‐M
Published: March 2004

Abstract: Systemic lupus erythematosus (SLE) is characterized by the production of autoantibodies directed against several nuclear components, such as DNA and histones. Apoptosis was induced in activated human lymphoblasts (n= 6) by UV‐B irradiation for 30 sec followed by continuous culturing. An extranuclear accumulation of the nucleosomal histones H2A, H2B, H3, and H4 in cell lysates was observed very early in the process of apoptosis, even before phosphatidylserine externalization occurred on the outer membrane surface of apoptotically dying lymphoblasts. We hypothesize that a dysregulation of apoptosis during these early phases may contribute to the induction of autoimmunity against nuclear autoantigens as seen in SLE.
Thallium Induces Apoptosis in Jurkat Cells
Authors: BRAGADIN MARCANTONIO , TONINELLO ANTONIO , BINDOLI ALBERTO , RIGOBELLO MARIA PIA , CANTON MARCELLA
Published: March 2004

Abstract: Thallium induces swelling in mitochondria and apoptosis in Jurkat cells. Both the swelling and the apoptosis are inhibited by means of cyclosporine A (CsA), thus suggesting that these phenomena result from the opening of the membrane transition pore (MTP) in mitochondria. Therefore, apoptosis can be explained as due to the opening of the MTP in mitochondria.
Triggering of T‐Cell Apoptosis by Toxin‐Related Ecto‐ADP‐Ribosyltransferase ART2
Authors: SCHEUPLEIN FELIX , ADRIOUCH SAHAHIL , GlOWACKI GUSTAVO , HAAG FRIEDRICH , SEMAN MICHEL , KOCH‐NOLTE FRIEDRICH
Published: March 2004

Abstract: Cytotoxicity induced by protein ADP‐ribosylation is a common theme of certain bacterial toxins and of the mammalian ectoenzyme ART2. Exposure of T cells to NAD, the substrate for ART2‐catalyzed ADP‐ribosylation, induces exposure of phosphatidylserine, uptake of propidium iodide, and fragmentation of DNA. ART2‐specific antibodies raised by gene gun immunization block NAD‐induced apoptosis. ART2 catalyzed ADP‐ribosylation of cell membrane proteins induces formation of cytolytic membrane pores by activating the P2X7 purinoceptor. This alternative pathway to T cell apoptosis could be triggered upon the release of NAD from intracellular stores, for example, during inflammatory tissue damage.
Effect of Zinc on Prostatic Tumorigenicity in Nude Mice
Authors: FENG PEI , LI TIE LUO , GUAN ZHI XIN , FRANKLIN RENTY B. , COSTELLO LESLIE C.
Published: March 2004

Abstract: Prostate epithelial cells accumulate the highest zinc levels of any cells in the body. Evidence indicates that zinc plays critical roles in the normal function and pathology of the prostate gland. We have identified two important effects of zinc in the prostate epithelial cells: the inhibition of m‐aconitase and the induction of mitochondrial apoptogenesis. However, at the present time, the effects of zinc on prostatic cells in in vivo conditions have not yet been reported. The objectives of this in vivo study were to investigate the effect of zinc on: tumorogenicity in nude mice, zinc accumulation in tumor tissues, and the levels of mitochondrial membrane permeability related proteins, Bax/Bcl‐2. A tumorigenicity animal model was established using male nude mice (4–6 weeks old) with inoculation of PC‐3 cells (5–10×106/mL) prepared in 10% Matrigel. The mice were treated with zinc by ALZET osmotic pumps (Durect Corporation), with a releasing rate of 0.25 μl/h for 28 days. Zinc concentrations of the tumor tissues were determined by Atomic Absorption Spectrophotometer method. Frozen sections of tumor tissues were prepared for TUNEL assay. The levels of Bax and Bcl‐2 in the tumor tissues were determined by Western blot analyses. Our study demonstrated that in vivo treatment of zinc increased zinc accumulation and citrate production in PC‐3 cell induced tumor tissues and inhibited tumor growth. The inhibitory effect of zinc appears to result from zinc‐induced apoptosis by regulation of mitochondrial membrane permeability‐related Bax/Bcl‐2 proteins.
Ultraviolet Ray Induces Chromosomal Giant DNA Fragmentation Followed by Internucleosomal DNA Fragmentation Associated with Apoptosis in Rat Glioma Cells
Authors: HIGUCHI YOSHIRO , MIZUKAMI YUJI , YOSHIMOTO TANIHIRO
Published: March 2004

Abstract: Giant DNA fragments (1–2 Mbp) were found in C6 rat glioma cells irradiated by a lethal dose of ultraviolet‐C (UV‐C, 254 nm) at 50 J/m2. After irradiation, the fragments mutated into high‐molecular‐weight (100–800 kbp) DNA fragments and then into ladder‐formed internucleosomal DNA fragments. Poly‐ADP‐ribose polymerase (PARP) activity and NAD levels were reduced during DNA fragmentation. Some inhibitors of caspase and protease inhibited DNA ladder formation, but not giant DNA fragmentation, whereas antioxidants did not inhibit DNA fragmentation. These results suggest that a lethal dose of UV radiation induces giant DNA fragmentation and leads to internucleosomal DNA fragmentation associated with apoptosis through some caspases and nonreactive oxygen species in cells.
The Antiproliferative Alkylphospholipid S‐1‐O‐Phosphocholine‐2‐N‐Acetyl‐Octadecane Induces Apoptosis in Leukemia Cell Lines
Authors: KRUG H F. , OBERLE C , MATZKE A , MASSING U
Published: March 2004

Abstract: Lipids are involved in a multitude of important cellular functions. They act as signaling molecules and can even provoke apoptosis. In this context we investigated the efficacy of synthetic alkylphosphocholines (APCs) as potential anti‐cancer membrane‐affecting drugs. Leading to novel therapeutic strategies for cancer treatment, the new agents interact with the cell membrane and do not affect the DNA. The data presented here show a cell death‐inducing capacity for 1‐O‐phosphocholine‐2[S]‐O‐acetyl‐octadecane and 1‐O‐phosphocholin‐2[S]‐N‐acetyl‐octadecane in Jurkat T cells as well as in BJAB cells. The activation of caspases is generally required for the induction of apoptosis as shown by experiments with specific caspase inhibitors. The results point on the one hand to the formation of a functional DISC after APC‐treatment as indicated by the clustering of receptor molecules and on the other hand to the dependency on the instrinsic apoptotic machinery and the downstream of mitochondria‐activated apoptosome.
Inhibition of Apoptosis by Amphiregulin via an Insulin‐like Growth Factor‐1 Receptor—Dependent Pathway in Non‐Small Cell Lung Cancer Cell Lines
Authors: HURBIN AMANDINE , DUBREZ LAURENCE , COLL JEAN‐LUC , FAVROT MARIE C.
Published: March 2004

Abstract: The reciprocal activation of amphiregulin (AR) and insulin‐like growth factor‐1 (IGF1) pathways has been shown to induce inhibition of serum deprivation apoptosis in non‐small cell lung cancer (NSCLC) cell lines H358 and H322. We demonstrated that AR activated the IGF1 receptor (IGF1‐R), which in turn induced the secretion of AR and IGF1. Transactivation of the IGF1‐R by AR is independent of its binding to EGFR. Thus, AR can inhibit apoptosis in NSCLC cells through an IGF1‐R‐dependent pathway.
Alveolar Cell Death in Hyperoxia‐Induced Lung Injury
Authors: PAGANO ALESSANDRA , BARAZZONE‐ARGIROFFO CONSTANCE
Published: March 2004

Abstract: Exposure to high oxygen concentration causes direct oxidative cell damage through increased production of reactive oxygen species. In vivo oxygen‐induced lung injury is well characterized in rodents and has been used as a valuable model of human respiratory distress syndrome. Hyperoxia‐induced lung injury can be considered as a bimodal process resulting (1) from direct oxygen toxicity and (2) from the accumulation of inflammatory mediators within the lungs. Both apoptosis and necrosis have been described in alveolar cells (mainly epithelial and endothelial) during hyperoxia. While the in vitro response to oxygen seems to be cell type‐dependent in tissue cultures, it is still unclear which are the death mechanisms and pathways implicated in vivo. Even though it is not yet possible to distinguish unequivocally between apo‐ptosis, necrosis, or other intermediate form(s) of cell death, a great variety of strategies has been shown to prevent alveolar damage and to increase animal survival during hyperoxia. In this review, we summarize the different cell death pathways leading to alveolar damage during hyperoxia, with particular attention to the pivotal role of mitochondria. In addition, we discuss the different protective mechanisms potentially interfering with alveolar cell death.
Na/Ca Exchanger Overexpression Induces Endoplasmic Reticulum Stress, Caspase‐12 Release, and Apoptosis
Authors: DÍAZ‐HORTA OSCAR , VAN EYLEN FRANÇOISE , HERCHUELZ ANDRÉ
Published: March 2004

Abstract: This paper describes a possible strategy to control Ca2+ homeostatsis as a possible approach to prevent or enhance β‐cell apoptosis
Cytochrome c, Glutathione, and the Possible Role of Redox Potentials in Apoptosis
Authors: HANCOCK JOHN T. , DESIKAN RADHIKA , NEILL STEVEN J.
Published: March 2004

Abstract: The redox environment of the cell is now thought to be extremely important to control the activity of many proteins. During apoptosis, the intracellular redox potential (Eh) becomes more positive, with possible consequences for the mechanisms of apoptosis. Glutathione and cytochrome c might both influence and be influenced by the cellular redox environment and therefore be important in the progression of apoptosis.
Inhibition of HSP70 and a Collagen‐Specific Molecular Chaperone (HSP47) Expression in Rat Osteoblasts by Microgravity
Authors: KUMEI YASUHIRO , MORITA SADAO , SHIMOKAWA HITOYATA , OHYA KEI'ICHI , AKIYAMA HIDEO , HIRANO MASAHIKO , SAMS CLARENCE F. , WHITSON PEGGY A.
Published: March 2004

Abstract: Rat osteoblasts were cultured aboard a space shuttle for 4 or 5 days. Cells were exposed to 1α, 25 dihydroxyvitamin D3 during the last 20 h and then solubilized by guanidine solution. The mRNA levels for molecular chaperones were analyzed by semi‐quantitative RT‐PCR. ELISA was used to quantify TGF‐β1 in the conditioned medium. The HSP70 mRNA levels in the flight cultures were almost completely suppressed, as compared to the ground (1 ×g) controls. The inducible HSP70 is known as the major heat shock protein that prevents stress‐induced apoptosis. The mean mRNA levels for the constitutive HSC73 in the flight cultures were reduced to 69%, ∼ 60% of the ground controls. HSC73 is reported to prevent the pathological state that is induced by disruption of microtubule network. The mean HSP47 mRNA levels in the flight cultures were decreased to 50% and 19% of the ground controls on the 4th and 5th days. Concomitantly, the concentration of TGF‐β1 in the conditioned medium of the flight cultures was reduced to 37% and 19% of the ground controls on the 4th and 5th days. HSP47 is the collagen‐specific molecular chaperone that controls collagen processing and quality and is regulated by TGF‐β1. Microgravity differentially modulated the expression of molecular chaperones in osteoblasts, which might be involved in induction and/or prevention of osteopenia in space.
Gelsolin for Senescence‐Associated Resistance to Apoptosis
Authors: AHN JEONG SOO , JANG IK‐SOON , RHIM JI HEON , KIM KYUNGTAE , YEO EUI‐JU , PARK SANG CHUL
Published: March 2004

Abstract: One of the characteristics of the senescent cell is apoptotic resistance. Gelsolin, a Ca2+‐dependent actin regulatory protein, is believed to regulate the intracellular movements which are necessary for cell growth, proliferation, and differentiation. Recently, gelsolin was suggested to play a role in apoptotic resistance, which led us to examine its involvement in the apoptotic resistance of senescent cells. We found that the protein and mRNA levels of gelsolin were increased in senescent human diploid fibroblasts (HDFs). Gelsolin was intracellularly co‐localized to the actin stress fiber and distributed to the nucleus and mitochondria in old HDFs. To examine the anti‐apoptotic function of gelsolin in senescent HDFs, we tried to downregulate the expression of gelsolin by using antisense oligonucleotide in old HDFs. We then treated the senescent HDFs with the apoptosis‐inducing agent menadione. Downregulation of gelsolin in senescent HDFs resulted in increased sensitivity to menadione‐induced apoptotic cell death. This suggests that gelsolin plays a role in the apoptotic resistance observed in senescent HDFs.
An Age‐Associated Decrease in the Frequency of C4B*Q0 Indicates That Null Alleles of Complement May Affect Health or Survival
Authors: ARASON GUÐMUNDUR JOHANN , BOÐVARSSON SIGURDUR , ÞOR SIGURÐARSON SIGURÐUR , SIGURÐSSON GARÐAR , ÞORGEIRSSON GUÐMUNDUR , GUÐMUNDSSON SVEINN , KRAMER JUDIT , FÜST GEORG
Published: March 2004

Abstract: We studied the distribution of complement C4, C3, and factor B allotypes in 423 healthy Icelandic subjects from 17 to 89 years of age. A marked decrease was observed in the carrier frequency of variant alleles of complement C4B (C4B*Q0) and C3 (C3*F). These results confirm our previous observations on Hungarian subjects and suggest a negative effect of C4B*Q0 on health or survival.
T‐Cell Survival Regulator LKLF Is Not Involved in Inappropriate Apoptosis of Diabetes‐Prone BBDP Rat T Cells
Authors: DIESSENBACHER PHILIP , BARTELS KATRIN , KOCH‐NOLTE FRIEDRICH , HAAG FRIEDRICH
Published: March 2004

Abstract: Diabetes‐prone BB (dpBB) rats develop autoimmune insulin‐dependent diabetes mellitus (IDDM) at high frequency as a consequence of a defect in T cell development, caused by a mutation in a single gene locus on rat chromosome 4 (lyp) which has recently been identified as immune‐associated nucleotide 4 (ian4). A phenotype similar to dpBB rat lymphopenia has recently been described in the mouse as the result of the targeted inactivation of the gene for the transcription factor LKLF (Lung Krüppel‐like factor, KLF2) in the immune system. We cloned the LKLF gene of the rat and screened a panel of rat/hamster radiation hybrid cell lines to determine its chromosomal localization. We conclude that the LKLF gene is not defective in dpBB rats and that its expression is not compromised by the lyp mutation.
The Role of Apoptosis in Acetaminophen‐Induced Injury
Authors: KASS GEORGE E. N. , MACANAS‐PIRARD PATRICIA , LEE PAULINE C. , HINTON RICHARD H.
Published: March 2004

Abstract: Apoptosis plays a critical role in acetaminophen (AAP)‐induced hepatic injury, since inhibiting apoptosis also prevents the development of acute liver failure. In this study, the mechanism of apoptosis induction by AAP was investigated in the human hepatoblastoma cell line HuH7. AAP caused marked cytotoxicity in HuH7 cells as a result of apoptosis. Processing of execution caspases to their corresponding active fragments and cleavage of cytokeratin‐18 were observed, supporting a role of caspases in AAP‐induced apoptosis. The manifestation of apoptosis was preceded by a translocation of cytochrome c from mitochondria to the cytosol. In conclusion, AAP induces apoptosis in human hepatoblastoma HuH7 cells through mitochondrial cytochrome c release and caspase activation.
Redox‐Dependent Apoptosis in Human Endothelial Cells after Adhesion of Plasmodium falciparum‐Infected Erythrocytes
Authors: PINO PACO , VOULDOUKIS IOANNIS , DUGAS NATHALIE , HASSANI‐LOPPION GERALDINE , DUGAS BERNARD , MAZIER DOMINIQUE
Published: March 2004

Abstract: During Plasmodium falciparum infection leading to cerebral malaria, mechanisms such as cytokine generation and cytoadherence of parasitized red blood cells (PRBC) to post‐capillary venules are clearly involved. We demonstrated that PRBC adhesion to human lung endothelial cells (HLEC) upregulated TNF‐α superfamily genes and genes related to apoptosis and inflammation. Apoptosis was confirmed by standard techniques (annexin‐V binding, genomic DNA fragmentation, and caspases activation). This apoptotic process involved the cytoplasmic pathway from a death receptor (DR‐6, Fas, TNF‐R1) through caspase 8, and the mitochondrial pathway though Bad and caspase 9 activation. Oxidative stress has been implicated in apoptosis induction in various pathological models. Superoxide anion (O2•‐) is a key molecule in the oxidative stress pathway which can form peroxynitrites (ONOO‐) in association with nitric oxide (NO•). Even though the role of NO• in malaria physiopathology is still a matter of controversy, we demonstrated that PRBC‐induced apoptosis in endothelial cells is mediated through an oxidative stress pathway. The inhibition of NO• synthesis protected the endothelial cells suggesting a deleterious role for NO•. In addition, the superoxide dismutase mimetic, MnTBAP, also protected the HLEC against PRBC‐induced apoptosis, revealing the role of O2•‐ and ONOO‐.
Apoptosis Inversely Correlates with Rabies Virus Neurotropism
Authors: THOULOUZE MARIA‐ISABEL , LAFAGE MIREILLE , YUSTE VICTOR J. , KROEMER GUIDO , SUSIN SANTOS A. , ISRAEL NICOLE , LAFON MONIQUE
Published: March 2004

Abstract: We report that non‐neurotropic rabies virus (RV) strains, currently used to immunize wildlife against rabies, induces not only a caspase‐dependent apoptosis in the human lymphoblastoid Jurkat T cell line (Jurkat‐vect), but also a caspase‐independent pathway. Cell redistribution of the apoptosis‐inducing factor (AIF) was observed in Jurkat‐vect infected with RV vaccine strain. Bcl‐2 overproduction in Jurkat T cells (Jurkat‐Bcl‐2) abolished both caspase activation and AIF distribution. In contrast, strain of neurotropic RV did not induce apoptosis. The inverse correlation of the induction of apoptosis and the capacity of a virus strain to invade the brain suggests that blockage of apoptosis could be a strategy selected by neurotropic virus to favor its progression through the nervous system.
Does Nitric Oxide Synthase Contribute to the Pathogenesis of Alzheimer's Disease?
Authors: LAHIRI D K. , CHEN D , GE Y‐W , FARLOW M , KOTWAL G , KANTHASAMY A , INGRAM D K. , GREIG N H.
Published: March 2004

Abstract: Oxidative stress is a risk factor for Alzheimer's disease (AD) whose major hallmark includes brain depositions of the amyloid beta peptide (Aβ) derived from the β‐amyloid precursor protein (APP). Our aim was to determine whether or not excessive Aβ deposition would alter nitric oxide synthase (NOS) activity, and thereby affect NOS‐mediated superoxide formation. We compared NOS activity in brain extracts between Tg mice (expressing APP Swedish double mutation plus presenilin [PS‐1] and nontransgenic [nTg] mice. Five brain regions, including cerebral cortex, hippocampus, cerebellum, and striatum from both nTg and Tg mice showed a detectable level of neuronal (n) NOS activity. Cerebellar extracts from both nTg and Tg mice displayed the highest level of nNOS activity, which was fourfold higher than cortical extracts. Although there was an increase in nNOS activity in Tg brain extracts, this did not attain statistical significance. A similar result was obtained for inducible NOS levels. Our results suggest that excess levels of Aβ failed to both trigger NOS activity and change NOS levels.
A Proximal Gene Promoter Region for the β‐Amyloid Precursor Protein Provides a Link between Development, Apoptosis, and Alzheimer's Disease
Authors: LAHIRI D K. , GHOSH C , GE Y‐W
Published: March 2004

Abstract: Abnormalities in regulation of the β‐amyloid precursor protein (APP) gene might be a crucial factor in Alzheimer's disease (AD). Our aim is to study the role of a specific proximal APP promoter element under the apoptotic condition. Our transfection studies with APP promoter deletion constructs indicate that each cell type differently regulates promoter activity. The minimum region that was sufficient to drive basal promoter activity in neuronal PC12 and neuroblastoma SK‐N‐SH cells was −75/+104 and −47/+104 bp, respectively. In SK‐N‐SH cells, the −47/+104 construct displayed the highest promoter activity, and the −75/−46 region acted as a negative regulatory element. Results from the gel electrophoretic mobility shift assay (EMSA) indicate that the −75/−46 region binds to a distinct DNA‐protein complex with nuclear protein(s) from HeLa, PC12, NIH‐3T3, and neuroblastoma cells. EMSA results from HeLa cells, which were stimulated by serum starvation (SR), indicate a significant induction in the signal of the DNA‐protein complex from controls. EMSA results from PC12 cells, which were subjected to hypoxia, indicate a significant reduction in the signal. Our results suggest that the −75/−46 region binds to a protein that is upregulated in serum starvation, and downregulated in hypoxia. Because serum starvation contributes to the induction of apoptosis, these results suggest a role of the 30‐bp proximal APP promoter element in enhanced apoptotic neuronal cell death.
Tellurium Compound AS101 Induces PC12 Differentiation and Rescues the Neurons from Apoptotic Death
Authors: MAKAROVSKY D , KALECHMAN Y , SONINO T , FREIDKIN I , TEITZ S , ALBECK M , WEIL M , GEFFEN‐ARICHA R , YADID G , SREDNI B
Published: March 2004

Abstract: Parkinson's disease is characterized by the loss of dopaminergic neurons in the substantia nigra (SN). Studies show that anti‐apoptotic and neurotrophic agents are suitable candidates to prevent delayed cell death and/or restore neural function. Here we present the nontoxic immunomodulating compound AS101, which has the ability to induce neurite outgrowth and neural differentiation in PC12 cells. The present study shows that components of the ras signaling pathway are crucial for AS101‐induced PC12 differentiation. These include p21ras and its downstream effectors, c‐raf‐1 and MEK, as well as PI3K. Moreover, these components mediate AS101‐induced upregulation of p21waf, which is obligatory for AS101‐induced PC12 differentiation. Furthermore, nitric oxide plays a significant role in these AS101 activities. Finally, we show that AS101 prevents apoptosis of NGF‐differentiated PC12 cells after NGF withdrawal. Taken together, these results suggest that AS101 induces PC12 cell differentiation and survival by activating the ras‐ERK1/2 and ras‐PI3K signal transduction pathways, as well as inducing NO production. Our findings may be important in understanding the regulation of survival/apoptosis of neurons deprived of neurotropic support. Futhermore the data propose that AS101 may have clinical potential in the treatment of neurodegenerative disorders like Parkinson's disease.
Inhibition of CDKs: A Strategy for Preventing Kainic Acid‐Induced Apoptosis in Neurons
Authors: VERDAGUER E , JORDÀ ELVIRA G. , STRANGES ALESSANDRA , CANUDAS ANNA M. , JIMÉNEZ ANDRÉS , SUREDA FRANCESC X. , PALLÀS MERCÈ , CAMINS ANTONI
Published: March 2004

Abstract: Stimulation of ionotropic glutamate receptors are implicated in neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. Recently this has been demonstrated in the expression of cell cycle proteins in vulnerable neurons in Alzheimer's disease. Thus, the aim of the present study was to evaluate the expression of cell cycle proteins in cerebellar granule cells after stimulation of AMPA/KA receptors and likewise to study the neuroprotective effects of CDK inhibitors. Our results demonstrated that after a treatment with CDK inhibitors, a significant decrease in apoptotic nuclei induced by kainic acid was found in the presence of flavopiridol and 3‐ATA. We concluded that CDK activation is involved, at least, in part, in the pro‐apoptotic effects of kainic acid.
Peripheral Markers of Apoptosis in Parkinson's Disease
Authors: BLANDINI F , MANGIAGALLI A , COSENTINO M , MARINO F , SAMUELE A , RASINI E , FANCELLU R , MARTIGNONI E , RIBOLDAZZI G , CALANDRELLA D , FRIGO G M. , NAPPI G
Published: March 2004

Abstract: In this study, we measured the lymphocyte levels of proteins involved in apoptosis regulation, such as Bcl‐2, the peripheral benzodiazepine receptor (PBR), caspase‐3, and Cu/Zn superoxide dismutase (Cu/Zn SOD), in patients with Parkinson's disease (PD), either untreated or under therapy with dopaminergic agents (l‐Dopa alone or l‐dopa + dopamine agonists) and in healthy volunteers. All PD groups showed increased activity of caspase‐3, compared to controls, particularly those under treatment only with l‐Dopa. In this latter group, the increase in caspase‐3 activity was also paralleled by an increase in the concentration of Cu/Zn SOD. In addition, patients taking l‐Dopa + dopamine agonists showed marked decrease in Bcl‐2 levels and increased PBR expression, which seems in keeping with the hypothesis that PBR may be functionally related to Bcl‐2. In conclusion, we found clear modifications in the levels of proteins involved in the control of apoptosis in lymphocytes of PD patients. These changes were disease related but also modulated by the pharmacological treatment, which confirms the potential role of apoptosis in PD pathogenesis and the modulatory influence of dopaminergic agents.
Proteolytic Activation of Proapoptotic Kinase PKCδ Is Regulated by Overexpression of Bcl‐2
Authors: KANTHASAMY A G. , KITAZAWA M , KAUL S , YANG Y , LAHIRI D K. , ANANTHARAM V , KANTHASAMY A
Published: March 2004

Abstract: We previously demonstrated that the organochlorine pesticide dieldrin, a potential chemical risk factor for development of Parkinson's disease (PD), impairs mitochondrial function and promotes apoptosis in dopaminergic PC12 cells. We further demonstrated that caspase‐3‐dependent proteolytic activation of a member of the novel PKC family, protein kinase Cδ (PKCδ), contributes to apoptotic cell death in dopaminergic cells. In the present study, we report that the proapoptotic function of PKCδ can be regulated by overexpression of the mitochondrial anti‐apoptotic protein Bcl2 in dieldrin‐treated dopaminergic cells. Exposure to dieldrin (30 or 100 μM) for 3 h produced a dose‐dependent increase in caspase‐3 activation and DNA fragmentation in vector‐transfected PC12 cells. Overexpression of human Bcl‐2 in PC12 cells completely suppressed dieldrin‐induced caspase‐3 activation and DNA fragmentation. Furthermore, dieldrin‐induced proteolytic activation of PKCδ was also remarkably reduced in Bcl‐2‐overexpressed cells. Together, these results suggest that the proapoptotic function of PKCδ can be regulated by mitochondrial redox modulators during neurodegenerative processes.
Oxidation of LDL, Atherogenesis, and Apoptosis
Authors: NAPOLI CLAUDIO
Published: March 2004

Abstract: A plethora of studies in cultured cells have established that oxidized low‐density lipoprotein (oxLDL) may enhance arterial apoptosis that involves both mitochondrial and death receptor pathways (Fas/FasL, TNF receptors I and II), thereby activating caspase cascade and other proteases. When apoptosis is inhibited by Bcl‐2 overexpression, oxLDL may trigger necrosis through a calcium‐dependent pathway. Despite this effort, the pathophysiological relevance of apoptosis in vivo remains to be elucidated. In principle, apoptosis occurring in atherosclerotic areas could be involved in endothelial cell lining defects, necrotic core formation, and plaque rupture or fissuring. This complex pathogenic framework may favor coronary atherothrombotic events. To date, the pathogenic role of apoptosis in thrombosis is attractive, but a solid evidence is still needed. When the precise role of oxLDL in vascular programmed cell death occurring in vivo is clarified, this may aid in the development of novel therapeutic approaches to adverse atherogenesis and its clinical sequelae.
Glycoxidation of Low‐Density Lipoprotein Increases TUNEL Positivity and CPP32 Activation in Human Coronary Cells
Authors: DE NIGRIS FILOMENA , TAJANA GIANFRANCO , CONDORELLI MARIO , D'ARMIENTO FRANCESCO P. , SICA GIACOMO , LERMAN LILACH O. , NAPOLI CLAUDIO
Published: March 2004

Abstract: Apoptosis of arterial cells induced by oxidized low‐density lipoprotein (oxLDL) is thought to contribute to the progression of vascular dysfunction and atherogenesis. It is well established that diabetes mellitus is accompanied by both glycosylation and oxidation of LDL (glc‐oxLDL), but the biological effects of these modified lipoproteins are poorly understood. We demonstrate here for the first time that glc‐oxLDL increases TUNEL positivity and caspase‐3 activation (by Western blot and immunocytochemistry) of human coronary smooth muscle cells. Overall, these effects induced by glc‐oxLDL were greater than those achieved with oxLDL. Thus, glc‐oxLDL activated downstream apoptotic signaling. This may influence the evolution of atherogenesis and vascular complications in diabetes.
No Evidence of Correlation between p53 Codon 72 Polymorphism and Risk of Bladder or Breast Carcinoma in Tunisian Patients
Authors: MABROUK IMED , BACCOUCHE SAMI , EL‐ABED RYM , MOKDAD‐GARGOURI RAJA , MOSBAH ALI , SAÏD SALEM , DAOUD JAMEL , FRIKHA MOUNIR , JLIDI RACHID , GARGOURI ALI
Published: March 2004

Abstract: The TP53 gene, frequently mutated in human cancers, carries several polymorphisms. The one most informative and studied concerns codon 72; a single base changes the CGC (arginine) to CCC (proline). The arginine form was considered to be a significant risk factor in the development of cancer. However, various reports on this polymorphism are controversial. We carried out the same investigation in two groups of patients, a group with bladder cancer and another with breast cancer, and in healthy controls in two regions of our country, using an improved PCR‐RFLP method. The number of Arg/Arg, Arg/Pro, and Pro/Pro genotypes was as follows: 21, 23, 3 and 13, 19, 2 for patients (total 47) and controls (34), respectively, in the first group; 18, 9, 3 and 19, 26, 4 for patients (30) and controls (49), respectively, in the second group. Statistical analysis of the genotype and allele frequencies did not reveal any difference between patients and controls in both groups except for a weak difference between the homozygotes to heterozygotes in the second group with a chi square of 4.1 (P= 0.045); the number of breast cancer patients is actually low (30) and should be increased in order to assess such a conclusion. Our overall results are therefore not consistent with a high risk associated with TP53 codon 72 polymorphism in breast and in bladder cancers.
Apoptosis in Prostate Carcinomas after Short‐Term Treatment with Decapeptyl
Authors: SZENDE B , LOVÁSZ S , FARID P , ROMICS I
Published: March 2004

Abstract: Altogether, 40 patients with advanced prostate cancer received the LH‐RH analog, Decapeptyl (D), as monotherapy for 1 month. The dose of D was 3.75 mg/month, intramuscularly in microcapsules. Needle biopsy was taken from the prostate of 20 patients at 24 hours, of 10 patients at 7 days, and of 10 patients at 30 days after the injection. The biopsy samples were investigated for mitotic and apoptotic indices as well as expression of p53 and Ki67 in the tumor cells. The effect of the LH‐RH analog was manifested in very low and even absent mitotic activity in all points in time. The expression of mutant p53 was high (above 80%) in all 1‐day and 7‐day samples and in 8 of 10 samples taken 30 days after the start of the therapy. In 2 cases, the ratio of p53‐expressing tumor cells was 2% and 5%. At day 30, the previously high ratio of Ki67‐positive tumor cells decreased to 2–10% in 8 cases and showed focally higher values (70–90%) in 2 cases. Extremely high (90–100%) apoptosis could be registered in scattered foci of the tumor tissue in all samples taken 1 and 7 days after D injection. The other parts of the tumor tissue showed lower (1–5%) apoptotic activity. At day 30 after the injection, the same phenomenon was observed in 4 cases, but in 6 cases the apoptotic ratio became diffusely low (1–2%). Focal increase of apoptosis observed in the 1‐ and 7‐day samples may be attributed to the direct effect of the LH‐RH analog on tumor cells. The findings at day 30 indicate a considerable decrease in proliferating activity and, in the majority of cases, also in apoptotic activity, reflecting the effect of D on the pituitary‐gonadal axis.
Transition in organ function during the evolution of air-breathing;insights from Arapaima gigas, an obligate air-breathing teleost from the Amazon
Authors: Brauner C. J. , Matey V. , Wilson J. M. , Bernier N. J. , Val A. L.
Published: March 2004

The transition from aquatic to aerial respiration is associated with dramatic physiological changes in relation to gas exchange, ion regulation,acid–base balance and nitrogenous waste excretion. Arapaima gigas is one of the most obligate extant air-breathing fishes,representing a remarkable model system to investigate (1) how the transition from aquatic to aerial respiration affects gill design and (2) the relocation of physiological processes from the gills to the kidney during the evolution of air-breathing. Arapaima gigas undergoes a transition from water-to air-breathing during development, resulting in striking changes in gill morphology. In small fish (10 g), the gills are qualitatively similar in appearance to another closely related water-breathing fish (Osteoglossum bicirrhosum); however, as fish grow (100–1000 g), the inter-lamellar spaces become filled with cells, including mitochondria-rich(MR) cells, leaving only column-shaped filaments. At this stage, there is a high density of MR cells and strong immunolocalization of Na+/K+-ATPase along the outer cell layer of the gill filament. Despite the greatly reduced overall gill surface area, which is typical of obligate air-breathing fish, the gills may remain an important site for ionoregulation and acid–base regulation. The kidney is greatly enlarged in A. gigas relative to that in O. bicirrhosum and may comprise a significant pathway for nitrogenous waste excretion. Quantification of the physiological role of the gill and the kidney in A. gigas during development and in adults will yield important insights into developmental physiology and the evolution of air-breathing.
In vitrodelayed senescence of extirpated buds from zooids of the colonial tunicateBotryllus schlosseri
Authors: Rabinowitz Claudette , Rinkevich Baruch
Published: March 2004

In the colonial growth of botryllid ascidians, blastogenesis (bud formation) is a cyclical and synchronized developmental process characterized by a weekly rhythm of budding and apoptotic events. Very little is known about this cycle regulation and its control. In this study, the in vitrofate of developing buds and regressing zooids extirpated from Botryllus schlosseri colonies at different blastogenic stages were examined,revealing that stages `B' to `D' buds (but not stage `A' buds) developed new structures under in vitro conditions. These were mainly spheres (up to 1 mm in diameter) and epithelial monolayers around the attached buds. We also found that: (1) when attached spheres and epithelial monolayers appeared,the life expectancy of an isolated bud in vitro reached 50–60 days, five times the life expectancy of intact, in vivo developing zooids; (2) the life expectancy of in vitro buds that remained unattached to the substrates was at least 150 days; (3) after attaching to the substrates, buds obeyed a newly imposed developmental clock dictating up to 35 survival days for spheres and up to 14 days for epithelial monolayers; (4) the prevailing mode of death in vitro was necrotic, in contrast to the apoptotic mode of zooidal deterioration at the takeover phase of blastogenesis; (5) under in vitro conditions, degenerating zooids surprisingly produced epithelial monolayers within 3 weeks of culturing. Monolayers survived for up to 10 additional days, extending the lifespan of the degenerating zooids from a few hours to up to 1 month. We conclude that under in vitro conditions, not only are the underlying colonial growth mechanisms replaced by different developmental pathways, but also the internal colonial-level clocks programming death, are replaced by a new biological mechanism with different timetables.
Resetting the path integrator: a basic condition for route-based navigation
Authors: Etienne Ariane S. , Maurer Roland , Boulens Valérie , Levy Arik , Rowe Tiffany
Published: March 2004

During short excursions away from home, some mammals are known to update their position with respect to their point of departure through path integration (dead reckoning) by processing internal (idiothetic) signals generated by rotations and translations. Path integration (PI) is a continuously ongoing process in which errors accumulate. To remain functional over longer excursions, PI needs to be reset through position information from stable external references. We tested the homing behaviour of golden hamsters(Mesocricetus auratus W.) during hoarding excursions following a rotation of the arena and nest. In continuous darkness, the hamsters returned to their point of departure at the rotated nest, and therefore depended on PI only. In other trials, the animals were briefly presented with visual room cues during or at the end of the outward trip, visual cues being pitted by 67° or 98° against the animal's current self-generated position vector. After a fix, the animals headed for the usual (unrotated) nest location, as defined by room cues, independent of the timing of the fix. These results were obtained in two different geometrical settings and showed that,after the fix, the animals update their position, and not merely their head direction or internal compass, in a new reference frame. Thus, episodic fixes on familiar external references reset the PI and therefore greatly enhance the functional signification of navigation that is based on feedback information from locomotion.
Acclimation to hypothermic incubation in developing chicken embryos(Gallus domesticus)
Authors: Black Juli L. , Burggren Warren W.
Published: March 2004

Chronic exposure to a low incubation temperature clearly slows the development of poikilothemic chicken embryos (or any other poikilotherms), but little is known about the more subtle developmental effects of temperature,especially on physiological regulatory systems. Consequently, two populations of chicken embryos were incubated at 38°C and 35°C. When compared at the same development stage, incubation temperature had no significant impact on embryonic survival or growth. Moreover, the relative timing of major developmental landmarks (e.g. internal pipping), expressed as a percentage of development, was unaffected by temperature. The ability to maintain the rate of oxygen consumption(V̇O2) during an acute drop in ambient temperature (Ta) improved from Hamburger–Hamilton (HH) stages 39–40 to 43–44 in the 38°C but not the 35°C populations. Late stage (HH43–44) embryos incubated at 38°C could maintain V̇O2(approximately 27–33 μl g–1 min–1)during an acute drop in Ta to approximately 30°C. However, at the same stage 35°C embryos acutely measured at 38°C were unable to similarly maintain their V̇O2, which fell as soon as Ta reached 36°C. Thus, while hypothermic incubation does not affect gross development (other than would be predicted from a simple effect of Q10), there is a significant delay in the relative timing of the onset of thermoregulatory ability induced by hypothermic incubation.
Interactions between zooplankton feeding, photosynthesis and skeletal growth in the scleractinian coralStylophora pistillata
Authors: Houlbrèque Fanny , Tambutté Eric , Allemand Denis , Ferrier-Pagès Christine
Published: March 2004

We investigated the effect of zooplankton feeding on tissue and skeletal growth of the scleractinian coral Stylophora pistillata. Microcolonies were divided into two groups: starved corals (SC), which were not fed during the experiment, and fed corals (FC), which were abundantly fed with Artemia salina nauplii and freshly collected zooplankton. Changes in tissue growth, photosynthesis and calcification rates were measured after 3 and 8 weeks of incubation. Calcification is the deposition of both an organic matrix and a calcium carbonate layer, so we measured the effect of feeding on both these parameters, using incorporation of 14C-aspartic acid and 45Ca, respectively. Aspartic acid is one of the major components of the organic matrix in scleractinian corals. For both sampling times, protein concentrations were twice as high in FC than in SC (0.73 vs 0.42 mg P–1 cm–2skeleton) and chlorophyll c2 concentrations were 3–4 times higher in fed corals (2.1±0.3 μg cm–2). Cell specific density (CSD), which corresponds to the number of algal cells inside a host cell, was also significantly higher in FC (1.416±0.028) than in SC (1.316±0.015). Fed corals therefore displayed a higher rate of photosynthesis per unit area (Pgmax=570±60 nmol O2 cm–2 h–1and Ik=403±27 μmol photons m–2s–1). After 8 weeks, both light and dark calcification rates were twofold greater in FC (3323±508 and 416±58 nmol Ca2+ 2 h–1 g–1 dry skeletal mass)compared to SC (1560±217 and 225±35 nmol Ca2+ 2 h–1 g–1 dry skeletal mass, respectively,under light and dark conditions). Aspartic acid incorporation rates were also significantly higher in FC (10.44±0.69 and 1.36± 0.26%RAV 2 h–1 g–1 dry skeletal mass, where RAV is total radioactivity initially present in the external medium) than in SC(6.51±0.45 and 0.44±0.02%RAV 2 h–1g–1 dry skeletal mass under dark and light conditions,respectively). Rates of dark aspartic acid incorporation were lower than the rates measured in the light. Our results suggest that the increase in the rates of calcification in fed corals might be induced by a feeding-stimulation of organic matrix synthesis.
The cardiovascular responses of the freshwater turtleTrachemys scriptato warming and cooling
Authors: Galli Gina , Taylor E. W. , Wang Tobias
Published: March 2004

Seven freshwater turtles Trachemys scripta were instrumented with flow probes and cannulated for blood pressure measurements. The turtles were warmed from 24 to 34°C, and cooled down to 24°C, with and without atropine. Animals exhibited a hysteresis of heart rate and blood flow to both the pulmonary and systemic circulations, which was not cholinergically mediated. Blood pressure remained constant during both warming and cooling,while systemic resistance decreased during heating and increased during cooling, indicating a barostatic response. There was a large right-to-left(R–L) shunt during warming and cooling in untreated animals, which remained relatively constant. Atropinisation resulted in a large L–R shunt, which decreased during warming and increased during cooling. Nevertheless, heating rates were the same in untreated and atropinised animals, and cooling rates were significantly longer in atropinised animals,indicating that shunt patterns contribute little to heat exchange.
Higher-order Conformations of DNA Are Useful as Templates to Create Various Superstructural Poly(pyrrole) Morphologies
Authors: Bae Ah-Hyun , Hatano Tsukasa , Numata Munenori , Takeuchi Masayuki , Shinkai Seiji
Published: March 2004

It was found that plasmid DNA can act as an attractive template for oxidative polymerization of pyrrole and result in the novel higher-order superstructures composed of the conductive polymers. The TEM and SEM observation estabilished that poly(pyrrole) grows up to nanosized rod-like, circular, and supercoiled structures reflecting the higher-order conformation of plasmid DNA. The obtained polymer structures are drastically changed reflecting the controlled DNA morphologies used as their templates.
Two-Photon Absorption Cross-Sections of Fluorene Derivatives with Cationic Substituents
Authors: Kawamata Jun , Akiba Masaharu , Tani Takeharu , Harada Akinori , Inagaki Yoshio
Published: March 2004

Two novel fluorene derivatives having cationic substituents were synthesized. Two-photon absorption (TPA) properties of the derivatives were evaluated using the fluorescence-based technique with a femtosecond pulse emitted from a Ti:sapphire laser. Maximum TPA cross-sections of the compounds were estimated from the TPA spectra. TPA cross-sections of compounds with cationic substituents were found to be significantly larger than those of the compounds without cationic substituents.
Unprecedented Pendant Group Exchange of a Porphyrinato Platinum(II) in Benzonitrile
Authors: Araki Naoko , Obata Makoto , Ichimura Akio , Mikata Yuji , Yano Shigenobu
Published: March 2004

5-(4-cyanophenyl)-10,15,20-triphenylporphyrinato platinum(II) (3) and 5-(4-methoxycarbonylphenyl)-10,15,20-triphenylporphyrinato platinum(II) (2) were isolated from a reaction of 5-(4-methoxycarbonylphenyl)-10,15,20-triphenyl porphyrin (1) with K2[PtCl4] in benzonitrile. Seemingly, 3 was generated through the functional group substitution reaction of the phenyl group of tetraphenylporphyrin during platinum ion insertion into 1 and was characterized by 1H NMR, mass spectroscopy, elemental analysis, and X-ray crystallography.
Synthesis and Physical Nature of Fluorescent Photoaffinity Probe for the Bioorganic Studies on Tautomycin, a Protein Phosphatase Type 1 Selective Inhibitor
Authors: Kurono Masakuni , Isobe Minoru
Published: March 2004

Fluorescent photoaffinity probe, which possesses a dansyl amide functional group on the maleic moiety of tautomycin, was prepared in order to detect the trace amount of labeled peptides. The parent compound dramatically showed fluorescence quenching before the photoreaction due to the exciplex formation on the basis of the folded conformation. Several benzhydrol analogs, on the other hand, recovered the strong fluorescence; thus, this system could be employed for the photoaffinity labeling studies.
Immobilization of Gold Nanorods on the Glass Substrate by the Electrostatic Interactions for Localized Plasmon Sensing
Authors: Niidome Yasuro , Takahashi Hironobu , Urakawa Shinji , Nishioka Koji , Yamada Sunao
Published: March 2004

Gold nanorods (NRs) have two localized surface plasmon bands in the visible–near infrared region. We have succeeded in well-dispersed deposition and immobilization of the gold nanorods on the surface of a glass substrate by the electrostatic interactions. The outermost PDDA layer was effective to prevent the lateral diffusion of NRs on the PSS layer. The longitudinal plasmon band showed clear shifts with solvents in the near-infrared region.