Vol.12 No.1 March 2007

DOI: 10.2478/s11658-006-0050-2 Volume 12 (2007) pp 1-15
Title INFLUENCES OF LOVASTATIN ON MEMBRANE ION FLOW AND INTRACELLULAR SIGNALING IN BREAST CANCER CELLS
Authors Na Wei, Man Tian Mi* and Yong Zhou
Abstract Lovastatin, an inhibitor of cellular cholesterol synthesis, has an apparent anti-cancer property, but the detailed mechanisms of its anti-cancer effects remain poorly understood. We investigated the molecular mechanism of Lovastatin anti-tumor function through the study of its effect on membrane ion flow, gap junctional intercellular communication (GJIC), and the pathways of related signals in MCF-7 mammary cancer cells. After treatment for 24-72 h with 4, 8 or 16 µmol/L Lovastatin, cellular proliferation was examined via the MTT assay, and changes in membrane potential and cellular [Ca2+]i were monitored using confocal laser microscopy. In addition, the expression of plasma membrane calcium ATPase isoform 1 (PMCA1) mRNA was analyzed via RT-PCR, the GJIC function was examined using the scrape-loading dye transfer (SLDT) technique, and MAPK phosphorylation levels were tested with the kinase activity assay. The results showed that Lovastatin treatment significantly inhibited the growth of MCF-7 breast cancer cells. It also increased the negative value of the membrane potential, leading to the hyperpolarization of cells. Moreover, Lovastatin treatment continuously enhanced [Ca2+]i, although the levels of PMCA1 mRNA were unchanged. GJIC was also upregulated in MCF-7 cells, with transfer of LY Fluorescence reaching 4 to 5 rows of cells from the scraped line after treatment with 16 µmol/L Lovastatin for 72 h. Finally, downregulation of ERK1 and p38MAPK phosphorylation were found in Lovastatin-treated MCF-7 cells. It could be deduced that Lovastatin can induce changes in cellular hyperpolarization and intracellular Ca2+ distributions, and increase GJIC function. These effects may result in changes in the downstream signal cascade, inhibiting the growth of MCF-7 cells.
Keywords Lovastatin, Human breast cancer cells, Cellular membrane ion transfer, Gap junctional intercellular communication (GJIC), MAPK activity
Address and Contact Information Department of Nutrition and Food Hygiene, Third Military Medical University, Chongqing 400038, P.R. China
*Author for correspondence: e-mail: mimt@vip.sina.com
[Rozmiar: 1332 bajtów]

DOI: 10.2478/s11658-006-0056-9 Volume 12 (2007) pp 16-24
Title PRINS AND C-PRINS: PROMISING TOOLS FOR THE PHYSICAL MAPPING OF THE LUPIN GENOME
Authors Anna Kaczmarek, Barbara Naganowska* and Bogdan Wolko
Abstract Two molecular cytogenetics methods, PRINS (primed in situ DNA labeling) and C-PRINS (cycling PRINS), were optimized for the physical mapping of several types of DNA sequences on the mitotic chromosomes of the narrow-leafed lupin (Lupinus angustifolius L.). The fragment of the FokI element from Vicia faba was localised by indirect PRINS reaction. Two other sequences, fragments of the coding sequences of L. luteus and of L. angustifolius, were localised by indirect C-PRINS. These techniques are faster and more sensitive than FISH, and they allowed the mapping of short DNA fragments. The data obtained shows that both types of PRINS are valuable tools for chromosome identification in lupin.
Keywords PRINS, C-PRINS, Physical mapping, Chromosomes, Lupinus angustifolius L.
Address and Contact Information Institute of Plant Genetics, Polish Academy of Sciences, Strzeszyńska 34, 60-479 Poznań, Poland
*Author for correspondence. e-mail: bnag@igr.poznan.pl
[Rozmiar: 1332 bajtów]

DOI:10.2478/s11658-006-0052-0 Volume 12 (2007) pp 25 – 38
Title INDUCTION OF HEME OXYGENASE-1 AND HEAT SHOCK PROTEIN 70 IN RAT HEPATOCYTES: THE ROLE OF CALCIUM SIGNALING
Authors Malte Silomon, Inge Bauer*, Michael Bauer, Julia Nolting, Markus Paxian and Hauke Rensing
Abstract Stress response genes including heat shock proteins are induced under a variety of conditions to confer cellular protection. This study investigated the role of calcium signaling in the induction of two stress response genes, heme oxygenase-1/hsp32 and hsp70, in isolated rat hepatocytes. Both genes were induced by cellular glutathione depletion. This induction could be inhibited by BAPTA-AM. Culturing in a calcium-free medium prevented the induction of hsp70 gene expression after glutathione depletion without affecting heme oxygenase-1 gene expression. Thapsigargin increased the gene expression of heme oxygenase-1 but not that of hsp70. Thapsigargin-induced heme oxygenase-1 induction was completely inhibited by BAPTA-AM. Incubation with the Ca2+-ionophore A23187 augmented heme oxygenase-1 (two-fold) and hsp70 (5.2-fold) mRNA levels. Our data suggests a significant role of Ca2+- dependent pathways in the induction of the two stress genes. An increase in the cytoplasmic Ca2+ activity seems to play a key role in the cascade of signaling leading to the induction of the two genes. However, the source of Ca2+ that fluxes into the cytoplasm seems to be different. Our data provides evidence for a compartmentalization of calcium fluxes, i.e. the Ca2+ flux from intracellular stores (e.g. the endoplasmic reticulum) plays a major role in the induction of heme oxygenase-1. By contrast, Ca2+ flux from the extracellular medium seems to be a mechanism initiating the cellular signaling cascade leading to hsp70 gene induction.
Keywords Stress response genes, Hepatocytes, Calcium, Gene expression
Address and Contact Information Department of Anesthesiology and Critical Care Medicine, University of Saarland, 66421 Homburg/Saar, Germany
*Author for correspondence; e-mail: aiibau@uniklinik-saarland.de, phone: (+49) 6841 1622721, fax: (+49) 6841 1622833
[Rozmiar: 1332 bajtów]

DOI: 10.2478/s11658-006-0049-8 Volume 12 (2007) pp 39 - 50
Title HIGHLY FUSOGENIC CATIONIC LIPOSOMES TRANSIENTLY PERMEABILIZE THE PLASMA MEMBRANE OF HeLa CELLS
Authors Katarzyna Stebelska1, Paulina Wyrozumska1, Jerzy Gubernator2 and Aleksander F. Sikorski1,2
Abstract Cationic liposomes can efficiently carry nucleic acids into mammalian cells. This property is tightly connected with their ability to fuse with negatively charged natural membranes (i.e. the plasma membrane and endosomal membrane). We used FRET to monitor and compare the efficiency of lipid mixing of two liposomal preparations – one of short-chained diC14- amidine and one of long-chained unsaturated DOTAP – with the plasma membrane of HeLa cells. The diC14-amidine liposomes displayed a much higher susceptibility to lipid mixing with the target membranes. They disrupted the membrane integrity of the HeLa cells, as detected using the propidium iodide permeabilization test. Morphological changes were transient and essentially did not affect the viability of the HeLa cells. The diC14-amidine liposomes were much more effective at either inducing lipid mixing or facilitating transfection.
Keywords Cationic liposomes, Fusion, Transfection, Plasma membrane integrity
Address and Contact Information 1Laboratory of Cytobiochemistry, Institute of Biochemistry and Molecular Biology, University of Wrocław, Przybyszewskiego 63/77, 51-148 Wrocław, Poland,
2Academic Centre for Biotechnology of Lipid Aggregates, Przybyszewskiego 63/77, 51-148 Wrocław, Poland
*Author for correspondence; fax: +48 71 375 6208, e -mail: afsbc@ibmb.uni.wroc.pl
[Rozmiar: 1332 bajtów]

DOI: 10.2478/s11658-006-0059-6 Volume 12 (2007) pp 51 - 69
Title SPECTROSCOPIC STUDIES OF D-α-TOCOPHEROL CONCENTRATION-INDUCED TRANSFORMATION IN EGG PHOSPHATIDYLCHOLNE VESICLES
Authors Krzysztof Dwiecki1, Paweł Górnaś1, Agnieszka Wilk3, Małgorzata Nogala-Kałucka2 and Krzysztof Polewski1*
Abstract The effects of embedding up to 60 mol% of α-tocopherol (α-Toc) on the morphology and structure of the egg phosphatidylcholine (PC) membrane were studied using spectroscopic techniques. The resulting vesicles were subjected to turbidometric and dynamic light scattering measurements to evaluate their size distribution. The α-Toc intrinsic fluorescence and its quenching was used to estimate the tocopherol position in the membrane. Optical microscopy was used to visualize morphological changes in the vesicles during the inclusion of tocopherol into the 2 mg/ml PC membrane. The incorporation of up to 15 mol% of tocopherol molecules into PC vesicles is accompanied by a linear increase in the fluorescence intensity and the simultaneous formation of larger, multilamellar vesicles. Increasing the tocopherol concentration above 20 mol% induced structural and morphological changes leading to the disappearance of micrometer-sized vesicles and the formation of small unilamellar vesicles of size ranging from 30 to 120 nm, mixed micelles and non-lamellar structures.
Keywords Egg phosphatidylcholine, Tocopherol, Fluorescence, Vesicles, Optical microscopy, Dynamic light scattering
Address and Contact Information 1Department of Physics, ul. Wojska Polskiego 38/42, 60-637 Poznań, Poland,
2Department of Biochemistry and Food Analysis, ul. Mazowiecka 48, 60-623 Poznań, Poland; August Cieszkowski Agricultural University, Poznań, Poland,
3Institute of Physics, A. Mickiewicz University, 61-614 Poznań, Poland
*Author for correspondence; e-mail: polewski@au.poznan.pl
[Rozmiar: 1332 bajtów]

DOI: 10.2478/s11658-006-0060-0 Volume 12 (2007) pp 70 - 81
Title DIFFERENCES IN THE DEGREE OF INHIBITION OF NDP REDUCTASE BY CHEMICAL INACTIVATION AND BY THE THERMOSENSITIVE MUTATION nrdA101 IN Escherichia coli SUGGEST AN EFFECT ON CHROMOSOME SEGREGATION
Authors José Riola, Estrella Guarino, Elena C. Guzmán and Alfonso Jimenez-Sánchez*
Abstract NDP reductase activity can be inhibited either by treatment with hydroxyurea or by incubation of an nrdAts mutant strain at the non-permissive temperature. Both methods inhibit replication, but experiments on these two types of inhibition yielded very different results. The chemical treatment immediately inhibited DNA synthesis but did not affect the cell and nucleoid appearance, while the incubation of an nrdA101 mutant strain at the nonpermissive temperature inhibited DNA synthesis after more than 50 min, and resulted in aberrant chromosome segregation, long filaments, and a high frequency of anucleate cells. These phenotypes are not induced by SOS. In view of these results, we suggest there is an indirect relationship between NDP reductase and the chromosome segregation machinery through the maintenance of the proposed replication hyperstructure.
Keywords NDP reductase, Hyperstructure, Chromosome segregation, Hydroxyurea
Address and Contact Information Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura, 06080-Badajoz, Spain
*Author for correspondence; e-mail: a.jimenezsanchez@gmail.com
[Rozmiar: 1332 bajtów]

DOI: 10.2478/s11658-006-0048-9 Volume 12 (2007) pp 82 - 102
Title DECREASED PROTEIN NITRATION IN MACROPHAGES THAT OVEREXPRESS INDOLEAMINE 2, 3-DIOXYGENASE
Authors Derin B. Keskin1 * # , Brendan Marshall1, David Munn1, Andrew L. Mellor1 and Debra A. Gearhart2,3 *
Abstract The activity of indoleamine 2, 3-dioxygenase (IDO; E.C. 1.13.11.42) catalyzes the oxidative cleavage of tryptophan to form kynurenine. IDO activity consumes superoxide anions; therefore, we postulated that over-expression of IDO might mitigate superoxide-anion dependent, oxidative modification of cellular proteins in vitro. We prepared and characterized RAW 264.7 macrophages that were stably transfected with either an IDO expression vector or the control (empty) vector. We detected IDO mRNA, protein, and enzyme activity in the IDO-transfected macrophages, but not in the macrophages transfected with the empty vector. To generate superoxide anions in situ, we treated the IDO- and control-transfected cultures with xanthine or hypoxanthine, and then used ELISA methods to quantitate the relative levels of oxidatively modified proteins in total cell lysates. The levels of protein carbonyls were similar in IDO-transfected and vector-transfected macrophages; however, protein nitration was significantly less in IDO-transfected cells compared to control transfectants. In addition, steady-state levels of superoxide anions were significantly lower in the IDO-transfected cultures compared with control transfectants. Our results are consistent with the concept that, besides degrading tryptophan, IDO activity may protect cells from oxidative damage.
Keywords RAW 264.7 macrophages, Indoleamine 2, 3-dioxygenase, Oxidative stress, Protein oxidation, Superoxide anion
Address and Contact Information 1Institute of Molecular Medicine and Genetics,
2Cellular Biology and Anatomy, Medical College of Georgia, Augusta, GA 30912, USA,
3Department of Veterans Affairs Medical Center Medical Research Service, Augusta, Georgia, USA
*Authors for correspondence. Debra A. Gearhart, e-mail: dgearhar@mail.mcg.edu and Derin B. Keskin, e-mail: Derin_keskin@dfci.harvard.edu
#Current address: Dana Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
‡ Current address: Pharmacology and Toxicology, Medical College of Georgia, Augusta, GA 30912, USA
[Rozmiar: 1332 bajtów]

DOI: 10.2478/s11658-006-0054-y Volume 12 (2007) pp 103 - 110
Title GENETIC DIVERSITY OF SIRE-1 RETROELEMENTS IN ANNUAL AND PERENNIAL GLYCINE SPECIES REVEALED USING SSAP
Authors Catherine Chesnay1, Amar Kumar1 and Stephen R. Pearce2*
Abstract Sequence Specific Amplification Polymorphisms (SSAP) were used to measure the distribution and structure of SIRE-1 retroelement populations in annual and perennial Glycine species. For SSAP analysis, primers corresponding to a region immediately upstream of the 3’LTR of the soybean retroelement SIRE-1 were chosen. Analysis reveals that SIRE-1 is present throughout the Glycine genus and shows that the annual species have similar SIRE-1 populations whilst the perennial species have much more distinct and diverse populations. The high number of species-specific subgroups suggest that SIRE-1 has been active and evolving independently in each species during the course of Glycine evolution.
Keywords Glycine, Retroelement, SSAP, phylogeny, SIRE-1, copia
Address and Contact Information 1Scottish Crop Research Institute, Invergowrie, Dundee, DD2 5DA, U.K.
2School of Life-Sciences, University of Sussex, Brighton, BN1 9QG, U.K.
*Author for correspondence; e -mail: S.R.Pearce@sussex.ac.uk
[Rozmiar: 1332 bajtów]

DOI: 10.2478/s11658-006-0055-x Volume 12 (2007) pp 111 - 119
Title HOW INFLUENZA'S NEURAMINIDASE PROMOTES VIRULENCE AND CREATES LOCALIZED LUNG MUCOSA IMMUNODEFICIENCY
Authors Ajay Bhatia1 and Richard E. Kast2*
Abstract Neuraminidase (NA) is an enzyme coded for by the genome of influenza critical for its pathogenicity and survival. Three currently accepted roles for this NA in promoting influenza virulence are: 1. NA cleaves newly formed virus particles from the host cell membrane. Without NA, newly formed virus would remain attached to the cell within which it was produced. 2. NA prevents newly released virus particles from aggregating to each other, preventing clumping that would reduce dissemination. 3. NA promotes viral penetration of sialic acid-rich mucin that bathes and protects respiratory epithelium through which the virus must spread and replicate. We outline here previous research evidence of two further, albeit hypothetical, functions of NA that together could cause disruption the mucosa-IgA axis, creating localized partial immunosuppressed state, enhancing both influenza infection itself and secondary bacterial pneumonia: 4. IgA provides primary immunoglobulin defense of mucosal surfaces. The hinge region of IgA is normally sialylated. IgA denuded of sialic acid is recognized, bound, and cleared by hepatic asialoglycoprotein receptor (ASGPR). Thus, IgA exposed to free NA would be so denuded and have increased hepatic clearance. 5. NA removes sialic acid moieties from mucosa-residing gamma/delta T cells or IgA producing B cells. Previous work indicates desialylation of these lymphocytes' outer cell membrane results in altered homing, to bone marrow, away from mucosa. Currently marketed NA inhibitors oseltamivir (Tamiflu) and zanamivir (Relenza) are FDA approved in USA for influenza prophylaxis and treatment. These NA inhibitors lower incidence of secondary bacterial infection in cases where an influenza infection occurs despite their use. Moreover, they are ameliorative in patients with secondary bacterial infections treated with antibiotics, a benefit that surpasses the treatment of antibiotics alone. We interpret these last two points as indicating our ascription of localized immunosuppression to influenza's NA could be correct and lead to new treatments of infections generally.
Keywords Asialoglycoprotein receptor, IgA, Immunodeficiency, Influenza, Lymphocyte homing, Neuraminidase, Oseltamivir, Sialic acid, Zanamivir
Address and Contact Information 1Ohio State University, Department of Psychiatry, Harding Hospital, 1670 Upham Drive, Columbus OH, 43210 USA,
2University of Vermont, Department of Psychiatry, 2 Church Street, Burlington, VT 05401 USA
*Author for correspondence: email: rekast@email.com
[Rozmiar: 1332 bajtów]

DOI: 10.2478/s11658-006-0053-z Volume 12 (2007) pp 120 - 126
Title SIRE-1, A PUTATIVE PLANT RETROVIRUS IS CLOSELY RELATED TO A LEGUME TY1-COPIA RETROTRANSPOSON FAMILY
Authors Stephen R. Pearce*
Abstract SIRE-1 is a potential soybean retrovirus which has a gene order similar to Ty1-copia retrotransposons but also contains an envelope-like open reading frame (ORF), which is characteristic of retroviruses. PCR and Southern analysis reveals that SIRE-1 is closely related to a legume-wide family of envelope-lacking Ty1-copia group retrotransposons which suggests that SIRE-1 was formed by the recent acquisition of an envelope gene by a Ty1-copia retrotransposon.
Keywords Glycine max, Retroelement, RNAseH
Address and Contact Information 1School of Life-Sciences, Department of Biology and Environmental Science, University of Sussex, Falmer, Brighton, BN1 9QG, United Kingdom
*E -mail: S.R.Pearce@sussex.ac.uk
[Rozmiar: 1332 bajtów]

DOI: 10.2478/s11658-006-0058-7 Volume 12 (2007) pp 127 - 138
Title ISCHEMIC HEART FAILURE ENHANCES ENDOGENOUS MYOCARDIAL APELIN AND APJ RECEPTOR EXPRESSION
Authors Pavan Atluri, Kevin J. Morine, George P. Liao, Corinna M. Panlilio, Mark F. Berry, Vivian M. Hsu, William Hiesinger, Jeffrey E. Cohen and Y. Joseph Woo*
Abstract Apelin interacts with the APJ receptor to enhance inotropy. In heart failure, apelin-APJ coupling may provide a means of enhancing myocardial function. The alterations in apelin and APJ receptor concentrations with ischemic cardiomyopathy are poorly understood. We investigated the compensatory changes in endogenous apelin and APJ levels in the setting of ischemic cardiomyopathy. Male, Lewis rats underwent LAD ligation and progressed into heart failure over 6 weeks. Corresponding animals underwent sham thoracotomy as control. Six weeks after initial surgery, the animals underwent hemodynamic functional analysis in the presence of exogenous apelin-13 infusion and the hearts were explanted for western blot and enzyme immunoassay analysis. Western blot analysis of myocardial APJ concentration demonstrated increased APJ receptor protein levels with heart failure (1890750±133500 vs. 901600±143120 intensity units, n=8, p=0.00001). Total apelin protein levels increased with ischemic heart failure as demonstrated by enzyme immunoassay (12.0±4.6 vs. 1.0±1.2 ng/ml, n=5, p=0.006) and western blot (1579400±477733 vs. 943000±157600 intensity units, n=10, p=0.008). Infusion of apelin-13 significantly enhanced myocardial function in sham and failing hearts. We conclude that total myocardial apelin and APJ receptor levels increase in compensation for ischemic cardiomyopathy.
Keywords Apelin, G protein coupled receptor, APJ, Inotrope
Address and Contact Information Division of Cardiothoracic Surgery, Department of Surgery, University of Pennsylvania, Silverstein 4, 3400 Spruce St., Philadelphia PA 19104, USA
*Author for correspondence: e-mail: wooy@uphs.upenn.edu, phone: 215-662-2956, fax: 215-349- 5798
[Rozmiar: 1332 bajtów]

DOI: 10.2478/s11658-006-0057-8 Volume 12 (2007) pp 139 - 147
Title A PROTEOMIC ANALYSIS OF THE EFFECT OF MAPK PATHWAY ACTIVATION ON L-GLUTAMATE-INDUCED NEURONAL CELL DEATH
Authors Sunghyun Kang, Eun Young Kim, Young Jae Bahn, Jin Woong Chung, Do Hee Lee, Sung Goo Park, Tae-Sung Yoon, Byoung Chul Park and Kwang-Hee Bae*
Abstract Oxidative stress has been implicated in the pathogenesis of neuronal degenerative diseases. It is also widely known that oxidative stress induces mitogen-activated protein kinase (MAPK) signaling cascades. In this study, we used proteomic analysis to investigate the role of the MAPK pathway in oxidative stress-induced neuronal cell death. The results demonstrated that several proteins, including eukaryotic translation elongation factor 2 (eEF2) and enolase I, showed a differential expression pattern during the neuronal cell death process, and this was MAPK pathway dependent. Several chaperone and cytoskeletal proteins including heat shock protein 70, calreticulin, vimentin, prolyl 4-hydroxylase ß polypeptide, and transgelin 2 were up- or downregulated, despite their expressions not depending on the MAPK pathway. These findings strongly suggest that the expressions of proteins which play protective roles are independent of the MAPK pathway. On the other hand, eEF2 and enolase I may be the downstream targets of the MAPK pathway.
Keywords Apoptosis, HT22, MAPK, Oxidative stress, Reactive oxygen species, U0126
Address and Contact Information Korean Research Institute of Bioscience and Biotechnology (KRIBB), 52 Eoeun-Dong, Yusung-Gu, Daejeon, 305-333, Republic of Korea
*Author for correspondence; e-mail: khbae@kribb.re.kr, tel: 82-42-860-4268
[Rozmiar: 1332 bajtów]

DOI: 10.2478/s11658-006-0071-x Volume 12 (2007) pp 148
Title PLANT DEHYDRINS – TISSUE LOCATION, STRUCTURE AND FUNCTION
Authors Tadeusz Rorat*
Erratum Erratum to CMBL
DOI: 10.2478/s11658-006-0044-0

The original version of the article unfortunately contained mistake. The author wish to inform:

The reference "[Asghar, R. et al. Protoplasma 177 (1994) 87-94]" inserted in the Abstract part of the article entitled PLANT DEHYDRINS – TISSUE LOCATION, STRUCTURE AND FUNCTION by Tadeusz Rorat, published in the Cellular & Molecular Biology Letters 11 (2006) 536-556 has been incorrectly introduced.
Address and Contact Information Korean Research Institute of Bioscience and Biotechnology (KRIBB), 52 Eoeun-Dong, Yusung-Gu, Daejeon, 305-333, Republic of Korea
*E-mail: tror@igr.poznan.pl
[Rozmiar: 1332 bajtów]