The mitochondrial death/life regulator in apoptosis and necrosis.
AuthorsKroemer G,Dallaporta B,Resche-Rigon M
JournalAnnual review of physiology
PubMed ID9558479
Both physiological cell death (apoptosis) and, in some cases, accidental cell death (necrosis) involve a two-step process. At a first level, numerous physiological and some pathological stimuli trigger an increase in mitochondrial membrane permeability. The mitochondria release apoptogenic factors through the outer membrane and dissipate the electrochemical gradient of the ... More
2,4 Dinitrophenol-uncoupling effect on delta psi in living hepatocytes depends on reducing-equivalent supply.
Mitochondrial uncouplers, such as 2,4 dinitrophenol (DNP), increase the cellular respiration by decreasing mitochondrial membrane potential (delta psi). We show that this respiratory effect can be transient or even prevented in isolated liver cells depending on the exogenous substrate used (dihydroxyacetone vs. octanoate or proline). Moreover the decrease in ATP/ADP ... More
Is rhodamine 123 an appropriate fluorescent probe to assess P-glycoprotein mediated multidrug resistance in vinblastine-resistant CHO cells?
Cellular drug resistance, which involves several mechanisms such as P-glycoprotein (P-gp) overexpression, kinetic and metabolic quiescence, or the increase in the intracellular levels of glutathione, limits the effectiveness of cancer treatment. It has been reported that functional assessment of the cationic dye rhodamin 123 (Rho123) efflux reveals accurately the drug-resistant ... More
Human epidermal cells progressively lose their cardiolipins during ageing without change in mitochondrial transmembrane potential.
Mitochondria dysfunction is considered to be a major cause of the modifications that occur during cell ageing. For this reason, cardiolipin, a suitable marker of the chondriome, as well as the mitochondrial transmembrane potential were examined in keratinocytes obtained from 9- to 75-year-old women. The study was carried out by ... More
Flow cytometric functional analysis of multidrug resistance by Fluo-3: a comparison with rhodamine-123.
AuthorsKoizumi S, Konishi M, Ichihara T, Wada H, Matsukawa H, Goi K, Mizutani S
JournalEur J Cancer
PubMed ID7488425
Using four cell lines including drug-sensitive K562/Parent cells, P-glycoprotein (Pgp)-mediated multidrug resistant (MDR) K562/VCR, K562/ADR and revertant K562/ADR-R cells, two fluorescent agents, Fluo-3 and rhodamine-123 (Rh-123), were compared as indicators in a functional assay of MDR. Cells were incubated with 4 microM Fluo-3 or 1 microM Rh-123 for 45 min ... More
Dyes providing increased sensitivity in flow-cytometric dye-efflux assays for multidrug resistance.
AuthorsFrey T, Yue S, Haugland RP
JournalCytometry
PubMed ID7587707
In an effort to improve detection of P-glycoprotein-mediated multidrug resistance (mdr), several dyes were compared to rhodamine 123 (R123) in efflux assays. Two dyes (SY-38 and SY-3150) were found that provided better sensitivity. These dyes were effluxed by a cell line known to be mdr-positive (P388/R84) but not by an ... More
Human (MDR1) and mouse (mdr1, mdr3) P-glycoproteins can be distinguished by their respective drug resistance profiles and sensitivity to modulators.
AuthorsTang-Wai DF, Kajiji S, DiCapua F, de Graaf D, Roninson IB, Gros P
JournalBiochemistry
PubMed ID7819214
Possible functional differences between P-glycoproteins (P-gps) encoded by the human MDR1 and mouse mdr1 and mdr3 genes with respect to drug resistance profiles and sensitivity to known modulators have been investigated. For this, the three genes were introduced and overexpressed in the same cellular background, that of Chinese hamster LR73 ... More
High-speed photodamage cell selection using bromodeoxyuridine/Hoechst 33342 photosensitized cell killing.
AuthorsHerweijer H, Stokdijk W, Visser JW
JournalCytometry
PubMed ID2452055
One of the major drawbacks of droplet sorting in a flow cytometer is the relatively low sorting speed. Thus, we have developed an alternative, faster sorting technique: photodamage cell sorting. In a photodamage cell sorter all unwanted cells, as detected with the first, measuring laser, are killed with the second, ... More
Localization of mitochondria in living cells with rhodamine 123.
AuthorsJohnson LV, Walsh ML, Chen LB
JournalProc Natl Acad Sci U S A
PubMed ID6965798
The laser dye rhodamine 123 is shown to be a specific probe for the localization of mitochondria in living cells. By virtue of its selectivity for mitochondria and its fluorescent properties, the detectability of mitochondria stained with rhodamine 123 is significantly improved over that provided by conventional light microscopic techniques. ... More
16HBE14o- human bronchial epithelial cell layers express P-glycoprotein, lung resistance-related protein, and caveolin-1.
AuthorsEhrhardt C, Kneuer C, Laue M, Schaefer UF, Kim KJ, Lehr CM
JournalPharm Res
PubMed ID12739760
PURPOSE: To study the expression of P-glycoprotein (P-gp), lung resistance-related protein (LRP), and caveolin-1 (cav-1) in the human bronchial epithelial cell line 16HBE14o-. METHODS: The presence of P-gp, LRP, and cav-1 in 16HBE14o- cell layers was evaluated using immunocytochemical staining and visualization with confocal laser scanning microscopy (CLSM). Functionality of ... More
Rapid assessment of physiological status in Escherichia coli using fluorescent probes.
AuthorsPorter J, Edwards C, Pickup RW
JournalJ Appl Bacteriol
PubMed ID7592133
'Rapid and direct viability assessment of Escherichia coli in filtered, sterile lake water was possible using multiparameter flow cytometry. Fluorescent dyes were used as probes for different cellular functions (membrane potential, membrane integrity and intracellular enzyme activity), which were correlated with the ability of the cells to respond to nutrient ... More
Tamoxifen but not 4-hydroxytamoxifen initiates apoptosis in p53(-) normal human mammary epithelial cells by inducing mitochondrial depolarization.
AuthorsDietze EC, Caldwell LE, Grupin SL, Mancini M, Seewaldt VL
JournalJ Biol Chem
PubMed ID11094056
'Despite the widespread clinical use of tamoxifen as a breast cancer prevention agent, the molecular mechanism of tamoxifen chemoprevention is poorly understood. Abnormal expression of p53 is felt to be an early event in mammary carcinogenesis. We developed an in vitro model of early breast cancer prevention to investigate how ... More
Nitric oxide induces tyrosine nitration and release of cytochrome c preceding an increase of mitochondrial transmembrane potential in macrophages.
AuthorsHortelano S, Alvarez AM, Boscá L
JournalFASEB J
PubMed ID10593878
'Treatment of elicited peritoneal macrophages or the macrophage cell line RAW 264.7 with high concentrations of nitric oxide donors is followed by apoptotic cell death. Analysis of the changes in the mitochondrial transmembrane potential (DeltaPsi(m)) with specific fluorescent probes showed a rapid and persistent increase of DeltaPsi(m), a potential that ... More
Targeting of the c-Abl tyrosine kinase to mitochondria in the necrotic cell death response to oxidative stress.
AuthorsKumar S, Bharti A, Mishra NC, Raina D, Kharbanda S, Saxena S, Kufe D
JournalJ Biol Chem
PubMed ID11350980
'The ubiquitously expressed c-Abl tyrosine kinase is activated in the response of cells to genotoxic and oxidative stress. The present study demonstrates that reactive oxygen species (ROS) induce targeting of c-Abl to mitochondria. We show that ROS-induced localization of c-Abl to mitochondria is dependent on activation of protein kinase C ... More
Distinct Intracellular Signaling in Tumor Necrosis Factor-related Apoptosis-inducing Ligand- and CD95 Ligand-mediated Apoptosis.
Authors Velthuis Jurjen H L; Rouschop Kasper M A; De Bont Hans J G M; Mulder Gerard J; Nagelkerke J Fred;
JournalJ Biol Chem
PubMed ID11980895
'Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a potent inducer of apoptosis in tumor cells but not in healthy cells. Similar to CD95 ligand (CD95L), TRAIL signaling requires ligand-receptor interaction; the downstream signaling molecules, such as Fas-associated death domain and caspase-8, also seem similar. Using cells stably expressing TRAIL and ... More
Bcl-2 expression in synovial fibroblasts is essential for maintaining mitochondrial homeostasis and cell viability.
'The regulation of proliferation and cell death is vital for homeostasis, but the mechanism that coordinately balances these events in rheumatoid arthritis (RA) remains largely unknown. In RA, the synovial lining thickens in part through increased proliferation and/or decreased synovial fibroblast cell death. Here we demonstrate that the anti-apoptotic protein, ... More
Adenovirus-mediated overexpression of catalase in the cytosolic or mitochondrial compartment protects against cytochrome P450 2E1-dependent toxicity in HepG2 cells.
AuthorsBai J, Cederbaum AI
JournalJ Biol Chem
PubMed ID11071897
'Cytochrome P450 2E1 (CYP2E1) is an effective producer of reactive oxygen species such as superoxide radical and hydrogen peroxide, which may contribute to the development of alcohol liver disease or cytotoxicity. To investigate the protective role of catalase against CYP2E1-dependent cytotoxicity, E47 cells, a transfected HepG2 cell line overexpressing CYP2E1, ... More
Essential role of voltage-dependent anion channel in various forms of apoptosis in mammalian cells.
AuthorsShimizu S, Matsuoka Y, Shinohara Y, Yoneda Y, Tsujimoto Y
JournalJ Cell Biol
PubMed ID11266442
'Through direct interaction with the voltage-dependent anion channel (VDAC), proapoptotic members of the Bcl-2 family such as Bax and Bak induce apoptogenic cytochrome c release in isolated mitochondria, whereas BH3-only proteins such as Bid and Bik do not directly target the VDAC to induce cytochrome c release. To investigate the ... More
Kinesin-mediated organelle translocation revealed by specific cellular manipulations.
AuthorsFeiguin F, Ferreira A, Kosik KS, Caceres A
JournalJ Cell Biol
PubMed ID7962067
'The distribution of membrane-bound organelles was studied in cultured hippocampal neurons after antisense oligonucleotide suppression of the kinesin-heavy chain (KHC). We observed reduced 3,3''-dihexyloxacarbocyanine iodide (DiOC6(3)) fluorescent staining in neurites and growth cones. In astrocytes, KHC suppression results in the disappearance of the DiOC6(3)-positive reticular network from the cell periphery, ... More
Rapid movements of vimentin on microtubule tracks: kinesin-dependent assembly of intermediate filament networks.
AuthorsPrahlad V, Yoon M, Moir RD, Vale RD, Goldman RD
JournalJ Cell Biol
PubMed ID9763428
'The assembly and maintenance of an extended intermediate filament (IF) network in fibroblasts requires microtubule (MT) integrity. Using a green fluorescent protein-vimentin construct, and spreading BHK-21 cells as a model system to study IF-MT interactions, we have discovered a novel mechanism involved in the assembly of the vimentin IF cytoskeleton. ... More
Axonal transport of mitochondria along microtubules and F-actin in living vertebrate neurons.
AuthorsMorris RL, Hollenbeck PJ
JournalJ Cell Biol
PubMed ID8522592
'A large body of evidence indicates that microtubules (MTs) conduct organelle transport in axons, but recent studies on extruded squid axoplasm have suggested that actin microfilaments (MFs) may also play a role in this process. To investigate the separate contributions to transport of each class of cytoskeletal element in intact ... More
SM-20 is a novel mitochondrial protein that causes caspase-dependent cell death in nerve growth factor-dependent neurons.
AuthorsLipscomb EA, Sarmiere PD, Freeman RS
JournalJ Biol Chem
PubMed ID11060309
'Sympathetic neurons undergo protein synthesis-dependent apoptosis when deprived of nerve growth factor (NGF). Expression of SM-20 is up-regulated in NGF-deprived sympathetic neurons, and ectopic SM-20 is sufficient to promote neuronal death in the presence of NGF. We now report that SM-20 is a mitochondrial protein that promotes cell death through ... More
Hyperthermia-induced nuclear translocation of transcription factor YB-1 leads to enhanced expression of multidrug resistance-related ABC transporters.
AuthorsStein U, Jürchott K, Walther W, Bergmann S, Schlag PM, Royer HD
JournalJ Biol Chem
PubMed ID11369762
'Genotoxic stress leads to nuclear translocation of the Y-box transcription factor YB-1 and enhanced expression of the multidrug resistance gene MDR1. Because hyperthermia is used for the treatment of colon cancer in combination with chemoradiotherapy, we investigated the influence of hyperthermia on YB-1 activity and the expression of multidrug resistance-related ... More
Two-photon fluorescence absorption and emission spectra of dyes relevant for cell imaging.
AuthorsBestvater F, Spiess E, Stobrawa G, Hacker M, Feurer T, Porwol T, Berchner-Pfannschmidt U, Wotzlaw C, Acker H
JournalJ Microsc
PubMed ID12423261
'Two-photon absorption and emission spectra for fluorophores relevant in cell imaging were measured using a 45 fs Ti:sapphire laser, a continuously tuneable optical parametric amplifier for the excitation range 580-1150 nm and an optical multichannel analyser. The measurements included DNA stains, fluorescent dyes coupled to antibodies as well as organelle ... More
Bcl-xL regulates the membrane potential and volume homeostasis of mitochondria.
'Mitochondrial physiology is disrupted in either apoptosis or necrosis. Here, we report that a wide variety of apoptotic and necrotic stimuli induce progressive mitochondrial swelling and outer mitochondrial membrane rupture. Discontinuity of the outer mitochondrial membrane results in cytochrome c redistribution from the intermembrane space to the cytosol followed by ... More
Modulation of hexokinase association with mitochondria analyzed with quantitative three-dimensional confocal microscopy.
AuthorsLynch RM, Fogarty KE, Fay FS
JournalJ Cell Biol
PubMed ID1991789
'Hexokinase isozyme I is proposed to be associated with mitochondria in vivo. Moreover, it has been suggested that this association is modulated in coordination with changes in cell metabolic state. To test these hypotheses, we analyzed the subcellular distribution of hexokinase relative to mitochondria in paraformaldehyde-fixed astrocytes using immunocytochemistry and ... More
Nerve growth factor signaling regulates motility and docking of axonal mitochondria.
AuthorsChada SR, Hollenbeck PJ
JournalCurr Biol
PubMed ID15268858
'Axonal transport is thought to distribute mitochondria to regions of the neuron where their functions are required. In cultured neurons, mitochondrial transport responds to growth cone activity, and this involves both a transition between motile and stationary states of mitochondria and modulation of their anterograde transport activity. Although the exact ... More
Rapid assessment of P-glycoprotein inhibition and induction in vitro.
AuthorsPerloff MD, Störmer E, von Moltke LL, Greenblatt DJ
JournalPharm Res
PubMed ID12948015
'PURPOSE: Using rhodamine123 (RH123) cell exclusion. 17 clinically used compounds were screened for their inhibitory effect on P-glycoprotein (P-gp), which was compared with the drugs'' inhibitory activity against CYP3A4. The same assay was used to study induction of P-gp activity. METHODS: P-gp inhibition was assessed using RH123 accumulation into LS180V ... More
Secreted beta-amyloid precursor protein counteracts the proapoptotic action of mutant presenilin-1 by activation of NF-kappaB and stabilization of calcium homeostasis.
AuthorsGuo Q, Robinson N, Mattson MP
JournalJ Biol Chem
PubMed ID9575187
'Mutations in the presenilin-1 (PS-1) gene account for approximately 50% of the cases of autosomal dominant, early onset, inherited forms of Alzheimer's disease (AD). PS-1 is an integral membrane protein expressed in neurons and is localized primarily in the endoplasmic reticulum (ER). PS-1 mutations may promote neuronal degeneration by altering ... More
Analysis of P-glycoprotein-mediated membrane transport in human peripheral blood lymphocytes using the UIC2 shift assay.
AuthorsPark SW, Lomri N, Simeoni LA, Fruehauf JP, Mechetner E
JournalCytometry A
PubMed ID12766968
'BACKGROUND: During transport-associated adenosine triphosphate hydrolysis, P-glycoprotein (Pgp) undergoes conformation transitions detected by UIC2, a functional anti-Pgp monoclonal antibody. A newly developed UIC2 shift assay is based on increased UIC2 reactivity in the presence of Pgp substrates. All peripheral blood leukocytes express low Pgp levels. The existing antibody-based detection methods ... More
Functional in vitro assays for the isolation of cell transformation effector and suppressor genes.
'Malignant transformation may be viewed as an imbalance between signals inducing cell growth and signals leading to growth inhibition, differentiation, or senescence. A basic understanding of how these counterbalancing forces interact to regulate normal cell growth is the prerequisite to comprehending the mechanisms of tumorigenesis. Identification and characterization of the ... More
Inhibition of the bovine-heart mitochondrial F1-ATPase by cationic dyes and amphipathic peptides.
AuthorsBullough DA, Ceccarelli EA, Roise D, Allison WS
JournalBiochim Biophys Acta
PubMed ID2527062
'The bovine heart mitochondrial F1-ATPase is inhibited by a number of amphiphilic cations. The order of effectiveness of non-peptidyl inhibitors examined as assessed by the concentration estimated to produce 50% inhibition (I0.5) of the enzyme at pH 8.0 is: dequalinium (8 microM), rhodamine 6G (10 microM), malachite green (14 microM), ... More
Estradiol decreases retention of rhodamine 123 fluorescence in GH4C1 pituitary tumor cells.
AuthorsVan Itallie CM, Kieffer LJ, Carbone R, Dannies PS
JournalMol Endocrinol
PubMed ID2325664
'Rhodamine 123 is a lipophilic cationic fluorescent dye that localizes in mitochondria. We found that 17 beta-estradiol changes the ability of GH4C1 cells, clonal rat pituitary tumor cells, to retain rhodamine 123. Cells incubated with 10 micrograms/ml rhodamine 123 for 30 min at 37 C took up about equal amounts ... More
Rhodamine 123 inhibits import of rat liver mitochondrial transhydrogenase.
AuthorsLubin IM, Wu LN, Wuthier RE, Fisher RR
JournalBiochem Biophys Res Commun
PubMed ID3579920
'Rhodamine 123, a laser dye, has been demonstrated to inhibit import of the precursor to pyridine dinucleotide transhydrogenase into mitochondria in rat liver cells. When rat hepatocytes were labeled with 35[S] methionine in the presence of 0.4 mM rhodamine 123, the precursor to transhydrogenase was found to have a half-life ... More
Zonula occludens toxin increases the permeability of molecular weight markers and chemotherapeutic agents across the bovine brain microvessel endothelial cells.
AuthorsKaryekar CS, Fasano A, Raje S, Lu R, Dowling TC, Eddington ND
JournalJ Pharm Sci
PubMed ID12532391
'The purpose of this study was to examine the ability of Zonula occludens toxin (Zot) to reversibly open tight junctions in bovine brain microvessel endothelial cells (BBMECs) to enhance drug delivery via the paracellular pathway. Transport across BBMEC monolayers was examined for molecular weight markers and chemotherapeutic agents ([(14)C]sucrose, [(14)C]inulin, ... More
Rhodamine efflux patterns predict P-glycoprotein substrates in the National Cancer Institute drug screen.
AuthorsLee JS, Paull K, Alvarez M, Hose C, Monks A, Grever M, Fojo AT, Bates SE
JournalMol Pharmacol
PubMed ID7969041
'Fifty-eight cell lines in the National Cancer Institute drug screen were analyzed for their ability to efflux the fluorescent dye rhodamine 123 as a functional assay for P-glycoprotein (Pgp). Using flow cytometry, the rhodamine fluorescence was measured for each cell line under four incubation conditions, i.e., after accumulation in the ... More
Rhodamine-123 staining in hematopoietic stem cells of young mice indicates mitochondrial activation rather than dye efflux.
AuthorsKim M, Cooper DD, Hayes SF, Spangrude GJ
JournalBlood
PubMed ID9596656
'Low-intensity fluorescence of rhodamine-123 (Rh-123) discriminates a quiescent hematopoietic stem cell (HSC) population in mouse bone marrow, which provides stable, long-term hematopoiesis after transplantation. Rh-123 labels mitochondria with increasing intensity proportional to cellular activation, however the intensity of staining also correlates with the multidrug resistance (MDR) phenotype, as Rh-123 is ... More
Diazoxide triggers cardioprotection against apoptosis induced by oxidative stress.
AuthorsIchinose M, Yonemochi H, Sato T, Saikawa T
JournalAm J Physiol Heart Circ Physiol
PubMed ID12623783
'Although mitochondrial ATP-sensitive potassium (mitoK(ATP)) channels have been reported to reduce the extent of apoptosis, the critical timing of mitoK(ATP) channel opening required to protect myocytes against apoptosis remains unclear. In the present study, we examined whether the mitoK(ATP) channel serves as a trigger of cardioprotection against apoptosis induced by ... More
Vitamin E deficiency impairs the modifications of mitochondrial membrane potential and mass in rat splenocytes stimulated to proliferate.
AuthorsPieri C, Moroni F, Recchioni R
JournalFree Radic Biol Med
PubMed ID7511124
'This study was designed to evaluate the time-dependent changes of mitochondrial membrane potential and mass during Con-A-induced proliferation of splenic lymphocytes from rat fed a normal or a vitamin E deficient diet. Rhodamine 123 and Nonyl Acridine Orange were used as specific probes to monitor the membrane potential and mass ... More
Unique oxidative mechanisms for the reactive nitrogen oxide species, nitroxyl anion.
AuthorsMiranda KM, Espey MG, Yamada K, Krishna M, Ludwick N, Kim S, Jourd'heuil D, Grisham MB, Feelisch M, Fukuto JM, Wink DA
JournalJ Biol Chem
PubMed ID11042174
'The nitroxyl anion (NO-) is a highly reactive molecule that may be involved in pathophysiological actions associated with increased formation of reactive nitrogen oxide species. Angeli''s salt (Na2N2O3; AS) is a NO- donor that has been shown to exert marked cytotoxicity. However, its decomposition intermediates have not been well characterized. ... More
Energy-dependent accumulation of daunorubicin into subcellular compartments of human leukemia cells and cytoplasts.
AuthorsSlapak CA, Lecerf JM, Daniel JC, Levy SB
JournalJ Biol Chem
PubMed ID1350280
'Anthracycline accumulation was evaluated by flow cytometry or radiolabeled drug assays in cells and cytoplasts (enucleated cells) prepared from parental and multidrug-resistant human K562 leukemia cells. Treatment with energy inhibitors, such as dinitrophenol (DNP) or sodium azide/deoxyglucose, led to a marked decrease in daunorubicin accumulation in parental cells and cytoplasts. ... More
Thiol oxidation by 2,2'-dithiodipyridine causes a reversible increase in cytoplasmic free Ca2+ concentration in pancreatic beta-cells. Role for inositol 1,4,5-trisphosphate-sensitive Ca2+ stores.
AuthorsIslam MS, Kindmark H, Larsson O, Berggren PO
JournalBiochem J
PubMed ID9020865
'2,2''-Dithiodipyridine (2,2''-DTDP), a reactive disulphide that mobilizes Ca2+ from ryanodine-sensitive Ca2+ stores in muscle, induced a biphasic increase in cytoplasmic free Ca2+ concentration ([Ca2+]i) in pancreatic beta-cells loaded with fura 2. This increase consisted of an early transient followed by a second, slower, rise. The [Ca2+]i transient was dependent on ... More
Flow cytometric analysis of the effects of high protein diet on isolated rat liver mitochondria.
AuthorsO'Connor JE, Kimler BF, Vargas JL
JournalCell Tissue Kinet
PubMed ID3245955
'We have investigated changes that occur in mitochondria obtained from the livers of rats that had been maintained on a high protein diet (80% casein instead of 20%) for 6 months. Liver homogenates were separated by centrifugation into a mitochondrial fraction, a nuclear fraction and the supernatant fluid of the ... More
Fluorescent cationic probes of mitochondria. Metrics and mechanism of interaction.
AuthorsBunting JR, Phan TV, Kamali E, Dowben RM
JournalBiophys J
PubMed ID2605307
'Mitochondria strongly accumulate amphiphilic cations. We report here a study of the association of respiring rat liver mitochondria with several fluorescent cationic dyes from differing structural classes. Using gravimetric and fluorometric analysis of dye partition, we find that dyes and mitochondria interact in three ways: (a) uptake with fluorescence quenching, ... More
Evaluation of fluorescent dyes for the detection of mitochondrial membrane potential changes in cultured cardiomyocytes.
AuthorsMathur A, Hong Y, Kemp BK, Barrientos AA, Erusalimsky JD
JournalCardiovasc Res
PubMed ID10727661
'OBJECTIVE: Maintenance of the mitochondrial membrane potential (Deltapsim) is fundamental for the normal performance and survival of cells such as cardiomyocytes, that have a high energy requirement. Measurement of Deltapsim is therefore essential in order to develop an understanding of the molecular mechanisms controlling cardiomyocyte function. Here we have evaluated ... More
Transfersomes--a novel vesicular carrier for enhanced transdermal delivery: development, characterization, and performance evaluation.
AuthorsJain S, Jain P, Umamaheshwari RB, Jain NK
JournalDrug Dev Ind Pharm
PubMed ID14606665
'This work describes the use of a novel vesicular drug carrier system called transfersomes, which is composed of phospholipid, surfactant, and water for enhanced transdermal delivery. The transfersomal system was much more efficient at delivering a low and high molecular weight drug to the skin in terms of quantity and ... More
Multidrug resistance in androgen-independent growing rat prostate carcinoma cells is mediated by P-glycoprotein.
AuthorsSiegsmund MJ, Kreukler C, Steidler A, Nebe T, Köhrmann KU, Alken P
JournalUrol Res
PubMed ID9079744
'Prostate carcinomas are in general resistant against virtually all cytotoxic drugs. Up to now it has not been thoroughly evaluated whether specific resistance factors, such as the expression of the MDR1 gene, play a role in this multi-agent resistance and whether there is a link between drug resistance and hormone-independent ... More
The potassium channel opener (-)-cromakalim prevents glutamate-induced cell death in hippocampal neurons.
AuthorsLauritzen I, De Weille JR, Lazdunski M
JournalJ Neurochem
PubMed ID9326286
'(-)-Cromakalim, a typical K+-channel opener, prevents neuronal death induced by either glucose and oxygen privation or by high (100 microM) extracellular glutamate in primary cultures of hippocampus. (-)-Cromakalim has no effect on the earliest events associated with exposure to glutamate. It does not prevent the rapid rise of intracellular Ca2+, ... More
Cisplatin nephrotoxicity: decreases in mitochondrial protein sulphydryl concentration and calcium uptake by mitochondria from rat renal cortical slices.
AuthorsZhang JG, Lindup WE
JournalBiochem Pharmacol
PubMed ID8161341
'The effects of cisplatin on several aspects of the function of mitochondria isolated from the rat renal cortex have been investigated in vitro. Incubation of renal cortical slices with cisplatin (2 mM) caused a rapid loss of mitochondrial protein-SH followed by a substantial decrease in Ca2+ uptake by the mitochondria ... More
Use of nonyl acridine orange and rhodamine 123 to follow biosynthesis and functional assembly of mitochondrial membrane during L1210 cell cycle.
AuthorsLeprat P, Ratinaud MH, Maftah A, Petit JM, Julien R
JournalExp Cell Res
PubMed ID1688800
'Specific mitochondrial incorporation of 10 N-nonyl acridine orange (NAO) is demonstrated by subcellular fractionation of rat hepatocytes. Moreover, comparative studies with NAO and rhodamine 123 (Rh 123) prove that acridine orange-derivative uptake is independent of transmembrane mitochondrial potential, a property allowing its utilization for the assessment of mitochondrial membrane mass ... More
Interaction of LDS-751 and rhodamine 123 with P-glycoprotein: evidence for simultaneous binding of both drugs.
AuthorsLugo MR, Sharom FJ
JournalBiochemistry
PubMed ID16229491
'The P-glycoprotein efflux pump, an ABC superfamily member, can export a wide variety of hydrophobic drugs, natural products, and peptides from cells, powered by the energy of ATP hydrolysis. Transport substrates appear to first partition into the membrane and then interact with the protein within the cytoplasmic leaflet. Two drug ... More
Changes in mitochondrial rhodamine-123-fluorescence populations of rat hepatocytes in primary culture.
AuthorsHernandez-Berciano R, Garcia MV, Lopez-Mediavilla C, Orfao A, Medina JM
JournalExp Cell Res
PubMed ID8224011
'Flow cytometry analysis of mitochondria isolated from rat hepatocytes at different stages of development revealed two different rhodamine-123-stained fluorescence populations distinguishable by their main fluorescence channel. The high-fluorescence population (HFP) was minor, accounting for about 32, 33, and 23% of the total mitochondrial fraction in hepatocytes from preterm, term, and ... More
Differentiation of promyelocytic (HL-60) cells into mature granulocytes: mitochondrial-specific rhodamine 123 fluorescence.
AuthorsCollins JM, Foster KA
JournalJ Cell Biol
PubMed ID6572192
'Rhodamine 123, a fluorescent dye which binds as a result of the transmembrane potential, was used to stain the mitochondria of HL-60 cells, a cell line established from human promelocytic leukemia cells. The DMSO-induced differentiation of promyelocytic cells into mature granulocytes caused a fourfold decrease in fluorescence intensity that paralleled ... More
Rapid stimulation of rhodamine 123 efflux from multidrug-resistant KB cells by progesterone.
'Rhodamine 123 is a mitochondrial dye that is retained for prolonged periods by carcinoma cells. While investigating causes of retention of this dye, we found that 10 microM progesterone caused a rapid stimulation of efflux of rhodamine 123 within 15 min from KB V20C cells, which overexpress the multidrug resistance ... More
Dynamical change of mitochondrial DNA induced in the living cell by perturbing the electrochemical gradient.
AuthorsCoppey-Moisan M, Brunet AC, Morais R, Coppey J
JournalBiophys J
PubMed ID8913573
'Digital-imaging microscopy was used in conditions that allowed the native state to be preserved and hence fluorescence variations of specific probes to be followed in the real time of living mammalian cells. Ethidium bromide was shown to enter into living cells and to intercalate stably into mitochondrial DNA (mtDNA), giving ... More
Quantitative differential effects of rhodamine 123 on normal cells and human colon cancer cells by magnetic resonance spectroscopy.
AuthorsSinger S, Neuringer LJ, Thilly WG, Chen LB
JournalCancer Res
PubMed ID8242640
'Rhodamine 123 is a lipophilic cationic compound that is selectively taken up by cancer cell mitochondria. This compound is toxic to epithelial cancer cells in vitro and displays significant anticancer activity in vivo. However, the mechanism of action of rhodamine 123 in intact, actively metabolizing cell preparations is unknown. We ... More
Functional study of multidrug resistance with fluorescent dyes. Limits of the assay for low levels of resistance and application in clinical samples.
AuthorsCanitrot Y, Lahmy S, Buquen JJ, Canitrot D, Lautier D
JournalCancer Lett
PubMed ID8827047
'Fluorescent dyes such as rhodamine 123 (R123) and Hoechst 33342 (Ho342) have been widely used to characterize multidrug-resistance (MDR) phenotype cells in cell populations, on the basis of their reduced accumulation in resistant cells. Taking advantage of the high fluorescence quantum yield of R123 and Ho342 compared with that of ... More
Unusual retention of rhodamine 123 by mitochondria in muscle and carcinoma cells.
'Mitochondria in cardiac muscle cells and myoblast-fused myotubes display unusually long (3-5 days) retention times of rhodamine 123, a mitochondria-specific fluorescent probe, in living cells. Among 50 keratin-positive carcinoma or transformed epithelial cell lines tested, mitochondria with prolonged rhodamine 123 retention are detected in most of the transitional cell carcinoma, ... More
Energy transfer spectroscopy for measuring mitochondrial metabolism in living cells.
AuthorsSchneckenburger H, Gschwend MH, Strauss WS, Sailer R, Kron M, Steeb U, Steiner R
JournalPhotochem Photobiol
PubMed ID9230702
'Microscopic energy transfer spectroscopy was established using mixed solutions of reduced nicotinamide adenine dinucleotide (NADH) and the mitochondrial marker rhodamine 123 (R123). This method was applied to probe mitochondrial malfunction of cultivated endothelial cells from calf aorta incubated with various inhibitors of specific enzyme complexes of the respiratory chain. Autofluorescence ... More
Multidrug transporter activity in lymphocytes.
AuthorsElliott JI, Raguz S, Higgins CF,
JournalBr J Pharmacol
PubMed ID15492020
'Multidrug transporters play a dual role in haematopoietic cells, mediating the efflux of xenobiotics and regulating cell migration. For several reasons including the lack of specific antibodies, reports of multidrug transporter distribution on lymphocytes conflict. Murine B cells have been reported to completely lack transporter activity. Through analysis of parental ... More
Hematopoietic stem cell characterization by Hoechst 33342 and rhodamine 123 staining.
AuthorsBertoncello I, Williams B
JournalMethods Mol Biol
PubMed ID14976367
'A dual-dye efflux strategy utilizing the supravital dyes Hoechst 33342 (Ho) and rhodamine 123 (Rh123) is described and illustrated for the detection and analysis of hematopoietic stem cells in murine bone marrow. Mononuclear cells from bone marrow cell suspensions were incubated in a cocktail of Rh123 plus Ho, and both ... More
Mitochondrial membrane potential measurement in rat cerebellar neurons by flow cytometry.
AuthorsSureda FX, Escubedo E, Gabriel C, Comas J, Camarasa J, Camins A
JournalCytometry
PubMed ID9136758
'Mitochondrial membrane potential (MMP) in dissociated rat cerebellar neurons was measured using rhodamine 123 (Rh 123) as fluorescent dye, and flow cytometry. Dye distribution was studied by confocal scanning microscopy. Propidium iodide (PI)-marked cells (dead cells) were not stained by Rh 123, while the green fluorescence of living cells was ... More
CPT-11-induced cell death in leukemic cells is not affected by the MDR phenotype.
'CPT-11 is a topoisomerase I (Topo I) inhibitor which was initially described as active in multi-drug resistance (MDR) tumors. The MDR phenomenon is characterized by the overexpression of efflux pumps which are able to extrude a range of drugs non-related chemical or functionally. In this work, we treated leukemic cells ... More
Stimulation of lipid peroxidation increases the intracellular calcium content of isolated hepatocytes.
AuthorsAlbano E, Bellomo G, Parola M, Carini R, Dianzani MU
JournalBiochim Biophys Acta
PubMed ID2001414
'Lipid peroxidation induced in isolated rat hepatocytes by FeCl3 (0.1 mM) was associated with an increase in the cytosolic free Ca2+ and in the ionophore-mobilizable Ca2+ content of both mitochondrial and extramitochondrial (endoplasmic reticular) pools. Ca2+ accumulation was completely prevented by the antioxidants promethazine and vitamin E succinate and was ... More
Calorie restriction induces mitochondrial biogenesis and bioenergetic efficiency.
AuthorsLópez-Lluch G, Hunt N, Jones B, Zhu M, Jamieson H, Hilmer S, Cascajo MV, Allard J, Ingram DK, Navas P, de Cabo R
JournalProc Natl Acad Sci U S A
PubMed ID16446459
'Age-related accumulation of cellular damage and death has been linked to oxidative stress. Calorie restriction (CR) is the most robust, nongenetic intervention that increases lifespan and reduces the rate of aging in a variety of species. Mechanisms responsible for the antiaging effects of CR remain uncertain, but reduction of oxidative ... More
Glutathione influences the proliferation as well as the extent of mitochondrial activation in rat splenocytes.
AuthorsPieri C, Moroni F, Recchioni R
JournalCell Immunol
PubMed ID1423643
'The time-dependent changes of mitochondrial membrane potential and mass have been investigated on rat splenic lymphocytes stimulated with Con A in the presence and absence of reduced glutathione (GSH). Rhodamine-123 (Rh-123) and nonyl acridine orange (NAO) were used as specific dyes to monitor the membrane potential and mass of mitochondria, ... More
Synaptic physiology and mitochondrial function in crayfish tonic and phasic motor neurons.
AuthorsNguyen PV, Marin L, Atwood HL
JournalJ Neurophysiol
PubMed ID9242280
'Phasic and tonic motor neurons of crustaceans differ strikingly in their junctional synaptic physiology. Tonic neurons generally produce small excitatory postsynaptic potentials (EPSPs) that facilitate strongly as stimulation frequency is increased, and normally show no synaptic depression. In contrast, phasic neurons produce relatively large EPSPs with weak frequency facilitation and ... More
Measurement of mitochondrial membrane potential using fluorescent rhodamine derivatives.
AuthorsScaduto RC, Grotyohann LW
JournalBiophys J
PubMed ID9876159
'We investigated the use of rhodamine 123 (R123), tetramethylrhodamine methyl ester (TMRM), and tetramethylrhodamine ethyl ester (TMRE) as fluorescent probes to monitor the membrane potential of mitochondria. These indicator dyes are lipophilic cations accumulated by mitochondria in proportion to DeltaPsi. Upon accumulation, all three dyes exhibit a red shift in ... More
pABC11 (also known as MOAT-C and MRP5), a member of the ABC family of proteins, has anion transporter activity but does not confer multidrug resistance when overexpressed in human embryonic kidney 293 cells.
AuthorsMcAleer MA, Breen MA, White NL, Matthews N
JournalJ Biol Chem
PubMed ID10438534
'Several members of the ABC family of proteins have been implicated in multidrug resistance associated with cancer therapies. A novel member of this gene family, designated pABC11, has been identified using degenerate polymerase chain reaction. The full-length cDNA spans 5881 base pairs and encodes an open reading frame of 1437 ... More
Characterization of multidrug-resistant pituitary tumor cells.
AuthorsNelson EJ, Hinkle PM
JournalEndocrinology
PubMed ID1350759
'These studies were designed to investigate the role of P-glycoprotein in an endocrine cell line. Drug-resistant pituitary cells were obtained by growing GH4C1 cells in the presence of increasing concentrations of colchicine. Cells resistant to colchicine at 0.4 micrograms/ml, termed GH4C1/RC.4, exhibited the multidrug-resistance phenotype, as the LD50 values for ... More
Modulation of intracellular formation of reactive oxygen intermediates in peritoneal macrophages and microglia/brain macrophages by propentofylline.
'Ischemia-induced nerve cell death can partly be prevented by propentofylline, a pharmacon structurally related to xanthine derivates that interacts with the neuromodulatory function of endogenous adenosine. To evaluate a possible mechanism of neuroprotection by propentofylline, we studied its effect on the cellular production of reactive oxygen intermediates in microglial cells, ... More
Mitochondrial membrane potential differentiates cells resistant to apoptosis in hybridoma cultures.
AuthorsFollstad BD, Wang DI, Stephanopoulos G
JournalEur J Biochem
PubMed ID11054104
'Previous research has implicated mitochondrial physiology and, by extension, respiratory capacity in the initiation and progress of apoptosis of cells in culture and tissue environments. This hypothesis was tested by separating a hybridoma cell population into subpopulations of varying mitochondrial membrane potential (MMP) using Rhodamine 123 stain and fluorescence-activated cell ... More
Candida glabrata ATP-binding cassette transporters Cdr1p and Pdh1p expressed in a Saccharomyces cerevisiae strain deficient in membrane transporters show phosphorylation-dependent pumping properties.
AuthorsWada S, Niimi M, Niimi K, Holmes AR, Monk BC, Cannon RD, Uehara Y
JournalJ Biol Chem
PubMed ID12244114
'The expression and drug efflux activity of the ATP binding cassette transporters Cdr1p and Pdh1p are thought to have contributed to the recent increase in the number of fungal infections caused by Candida glabrata. The function of these transporters and their pumping characteristics, however, remain ill defined. We have evaluated ... More
Cross-resistance to rhodamine 123 in Adriamycin- and daunorubicin-resistant Friend leukemia cell variants.
AuthorsTapiero H, Munck JN, Fourcade A, Lampidis TJ
JournalCancer Res
PubMed ID6498816
'Cross-resistance to rhodamine 123 (Rho-123) has been found in Adriamycin (ADM)-resistant and daunorubicin (DNR)-resistant Friend leukemia cell variants. Cytotoxicity in sensitive cells correlates with the intracellular amount of Rho-123, as determined by high-pressure liquid chromatography. Differential resistance coincides with Rho-123 accumulation which in sensitive cells was 20-fold higher than in ... More
Effect of Bcl-2 on oxidant-induced cell death and intracellular Ca2+ mobilization.
AuthorsIchimiya M, Chang SH, Liu H, Berezesky IK, Trump BF, Amstad PA
JournalAm J Physiol
PubMed ID9730968
'The mechanism by which Bcl-2 inhibits cell death is unknown. It has been suggested that Bcl-2 functions as an antioxidant. Because Bcl-2 is localized mainly to the membranes of the endoplasmic reticulum (ER) and the mitochondria, which represent the main intracellular storage sites for Ca2+, we hypothesized that Bcl-2 might ... More
Functional characterization of human breast cancer resistance protein (BCRP, ABCG2) expressed in the oocytes of Xenopus laevis.
AuthorsNakanishi T, Doyle LA, Hassel B, Wei Y, Bauer KS, Wu S, Pumplin DW, Fang HB, Ross DD
JournalMol Pharmacol
PubMed ID14645676
'To evaluate the function and substrate specificity of human breast cancer resistance protein (BCRP, ABCG2) in the absence of cofactors or heterologous partner proteins, Xenopus laevis oocytes were injected with cRNA of wild-type or mutant (R482T) BCRP. High expression of BCRP was observed on the oocyte surface. Accumulation and efflux ... More
Rhodamine 123: a useful probe for monitoring T cell activation.
AuthorsFerlini C, Biselli R, Nisini R, Fattorossi A
JournalCytometry
PubMed ID8582251
'The T cell activation pathway involves an increase in mitochondrial activity. This can be evaluated in individual cells using the fluorescent probe rhodamine 123 (Rh123) and flow cytometry. Peripheral blood mononuclear cells (PBMC) were stimulated with optimal concentrations of phytohaemagglutinin (PHA), superantigens (Sag) SEA and SEC2, and allogeneic cells. Activation ... More
Interactions of pluronic block copolymers with brain microvessel endothelial cells: evidence of two potential pathways for drug absorption.
AuthorsMiller DW, Batrakova EV, Waltner TO, Alakhov VYu Kabanov AV
JournalBioconjug Chem
PubMed ID9327127
'Pluronic block copolymers have been previously reported to increase the delivery of agents to the brain [Kabanov et al. (1992) J. Controlled Release 22, 141-158]. In the present study, primary cultured bovine brain microvessel endothelial cells (BBMEC) were used as an in vitro model of the blood-brain barrier to examine ... More
Mitochondrial membrane potential is dependent on the oligomeric state of F1F0-ATP synthase supracomplexes.
AuthorsBornhövd C, Vogel F, Neupert W, Reichert AS
JournalJ Biol Chem
PubMed ID16551625
'The F1F0-ATP synthase in mitochondria, in addition to its function in energy transduction, has a structural role in determining cristae morphology. This depends on its ability to form dimeric and higher oligomeric supracomplexes. Here we show that mutants of the dimer-specific subunits e and g, which destabilize dimeric and oligomeric ... More
Penetration of Toxoplasma gondii into host cells induces changes in the distribution of the mitochondria and the endoplasmic reticulum.
Authorsde Melo EJ, de Carvalho TU, de Souza W
JournalCell Struct Funct
PubMed ID1473161
'Fluorescence microscopy, using dyes which specifically label mitochondria, endoplasmic reticulum and the Golgi complex, and transmission electron microscopy, were used to analyze the changes which occur in the organization of these structures during interaction of Toxoplasma gondii with host cells. In uninfected cells the mitochondria are long filamentous structures which ... More
Species-specific differences in the toxicity of rhodamine 123 towards cultured mammalian cells.
AuthorsGupta RS, Dudani AK
JournalJ Cell Physiol
PubMed ID3558490
'The toxicity of cationic fluorescent dye, rhodamine 123, towards a number of independently established cell lines from three different species, namely human, mouse, and Chinese hamster, has been examined. All of the cell lines from any one species that were examined were found to exhibit similar sensitivities towards rhodamine 123 ... More
The effects of mitochondrial energetics inhibitors on the fluorescence of potential-sensitive dyes rhodamine 123 and diS-C3-(5) in lymphocyte suspensions.
AuthorsMokhova EN, Rozovskaya IA
JournalJ Bioenerg Biomembr
PubMed ID3745149
'The effects of uncouplers (FCCP, DNF), oligomycin, and rotenone on the fluorescence of potential-sensitive dyes, rhodamine 123 and diS-C3-(5), in lymphocyte suspensions were compared. The fluorescence of these optical probes gradually increased at higher FCCP concentrations. The dependences of fluorescence intensities and FCCP concentrations were similar for both dyes, and ... More
Altered cytochrome c display precedes apoptotic cell death in Drosophila.
AuthorsVarkey J, Chen P, Jemmerson R, Abrams JM
JournalJ Cell Biol
PubMed ID10037791
'Drosophila affords a genetically well-defined system to study apoptosis in vivo. It offers a powerful extension to in vitro models that have implicated a requirement for cytochrome c in caspase activation and apoptosis. We found that an overt alteration in cytochrome c anticipates programmed cell death (PCD) in Drosophila tissues, ... More
Rhodamine 123-efflux from hematopoietic subpopulations and leukaemic blast populations marked by PerCP-conjugated monoclonal antibodies.
AuthorsBeck J, Gekeler V, Ringger M, Handgretinger R, Niethammer D
JournalCancer Lett
PubMed ID8616825
'A representative functional assay for determination of drug transporting proteins (e.g. P-glycoprotein) in leukaemic blasts could help to evaluate effects of chemotherapy combined with chemosensitizers. Since subpopulations of normal peripheral blood or bone marrow cells show distinct P-glycoprotein levels, the presence of these cells in leukaemic samples causes a major ... More
Interference of calmidazolium with measurement of mitochondrial membrane potential using the tetraphenylphosphonium electrode or the fluorescent probe rhodamine 123.
AuthorsSaris NE, Teplova VV, Odinokova IV, Azarashvily TS
JournalAnal Biochem
PubMed ID15113685
'Calmidazolium (CMZ) is a positively charged, hydrophobic compound used as a calmodulin antagonist. It may cause unspecific effects in mitochondria, e.g., a decrease in membrane potential (deltapsi), swelling, and uncoupling. Several groups have advised against use of CMZ in studying signal transduction in mitochondria. We report here that it interferes ... More
Evaluation of an immortalized retinal endothelial cell line as an in vitro model for drug transport studies across the blood-retinal barrier.
AuthorsShen J, Cross ST, Tang-Liu DD, Welty DF
JournalPharm Res
PubMed ID14567628
'PURPOSE: To evaluate the growth and barrier properties of an immortalized rat retinal endothelial cell line (TR-iBRB) maintained on permeable membrane for drug transport studies. METHODS: TR-iBRB cells were grown on permeable membrane filters. The effect of coating material on cell growth was investigated. Transport of [14C]-3-O-methyl-D-glucose (3-OMG), AGN 194716, ... More
Molecular evidence and functional expression of P-glycoprotein (MDR1) in human and rabbit cornea and corneal epithelial cell lines.
AuthorsDey S, Patel J, Anand BS, Jain-Vakkalagadda B, Kaliki P, Pal D, Ganapathy V, Mitra AK
JournalInvest Ophthalmol Vis Sci
PubMed ID12824231
'PURPOSE: Efflux pumps such as P-glycoprotein (P-gp; MDR1) are believed to be a major barrier to drug delivery. The purpose of this work was to determine whether cornea and corneal epithelial cells expresses the functionally active P-gp efflux pump. METHOD: Cultured rabbit primary corneal epithelial cells (rPCECs) and a corneal ... More
Methods for the assessment of mitochondrial membrane permeabilization in apoptosis.
AuthorsGalluzzi L, Zamzami N, de La Motte Rouge T, Lemaire C, Brenner C, Kroemer G
JournalApoptosis
PubMed ID17294081
'Mitochondrial membrane permeabilization (MMP) is considered as the "point-of-no-return" in numerous models of programmed cell death. Indeed, mitochondria determine the intrinsic pathway of apoptosis, and play a major role in the extrinsic route as well. MMP affects the inner and outer mitochondrial membranes (IM and OM, respectively) to a variable ... More
Hypertrophy of renal mitochondria.
AuthorsHwang S, Bohman R, Navas P, Norman JT, Bradley T, Fine LG
JournalJ Am Soc Nephrol
PubMed ID2133432
'Compensatory renal hypertrophy leads to an increase in the size and metabolic capacity of renal tubular cells. Increased transport and metabolic activities must be sustained by an augmented rate of energy production, which is largely dependent on mitochondrial processes. Although previous studies have suggested that mitochondria proliferate in the hypertrophying ... More
Reversal of P-glycoprotein-mediated multidrug resistance by ginsenoside Rg(3).
AuthorsKim SW, Kwon HY, Chi DW, Shim JH, Park JD, Lee YH, Pyo S, Rhee DK
JournalBiochem Pharmacol
PubMed ID12473381
'Multidrug resistance has been a major problem in cancer chemotherapy. In this study, in vitro and in vivo modulations of MDR by ginsenoside Rg(3), a red ginseng saponin, were investigated. In flow cytometric analysis using rhodamine 123 as an artificial substrate, Rg(3) promoted accumulation of rhodamine 123 in drug-resistant KBV20C ... More
Methylmercury increases intracellular concentrations of Ca++ and heavy metals in NG108-15 cells.
AuthorsHare MF, McGinnis KM, Atchison WD
JournalJ Pharmacol Exp Ther
PubMed ID8371160
'To determine if methylmercury (MeHg) increased [Ca++]i in intact neuron-like cells, we initiated studies using fluorescence microscopy of single NG108-15 cells preloaded with fura-2. Whereas at 0.5 microM, MeHg had no effect on the ratio of fura-2 fluorescence at 340/380 nm, at 2 and 5 microM it produced a biphasic ... More
Influence of dexniguldipine-HC1 on rhodamine-123 accumulation in a multidrug-resistant leukaemia cell line: comparison with other chemosensitisers.
AuthorsBoer R, Haas S, Schödl A
JournalEur J Cancer
PubMed ID7654442
'In the clinical therapy of cancer, resistance to many cytostatic drugs is a major cause of treatment failure. Among other mechanisms, the expression and pumping activity of P-glycoprotein (PGP) in the membrane of resistant cancer cells is responsible for the reduced uptake of cytostatics. The blockade or inhibition of PGP ... More
The impairment of mitochondrial membrane potential and mass in proliferating lymphocytes from vitamin E deficient animals is recovered by glutathione.
AuthorsPieri C, Recchioni R, Marcheselli F, Moroni F, Marra M, Benatti C
JournalCell Mol Biol (Noisy-le-grand)
PubMed ID8535168
'The time-dependent changes of mitochondrial membrane potential and mass have been investigated on splenocytes from control and vit. E deficient rats, stimulated to proliferate with Concanavalin A, in the presence and absence of reduced glutathione (GSH, 5 mM). Rhodamine-123 (Rh-123) and nonyl acridine orange (NAO) were used as specific probes ... More
Transmembrane inhibitors of P-glycoprotein, an ABC transporter.
AuthorsTarasova NI, Seth R, Tarasov SG, Kosakowska-Cholody T, Hrycyna CA, Gottesman MM, Michejda CJ
JournalJ Med Chem
PubMed ID15916428
'Drug resistance mediated by ABC transporters such as P-glycoprotein (P-gp) continues to be a major impediment to effective cancer chemotherapy. We have developed a panel of highly specific peptide inhibitors of P-gp based on the structure of the transmembrane domains of the transporter. These peptides are thought to exert their ... More
Mitochondrial polarisation status and [Ca2+]i signalling in rat cerebellar granule neurones aged in vitro.
AuthorsXiong J, Camello PJ, Verkhratsky A, Toescu EC
JournalNeurobiol Aging
PubMed ID15123341
'Mitochondrial membrane potential is a major factor that controls, ultimately, the cellular energy supply. By use of a mitochondrial membrane potential dye (rhodamine 123, R123) and image analysis we show that during long-term (>3 weeks) culture of primary neurones (cerebellar granule neurones) there is a gradual and time-dependent depolarisation of ... More
Selective toxicity of rhodamine 123 in carcinoma cells in vitro.
'The study of mitochondria in situ has recently been facilitated through the use of rhodamine 123, a mitochondrial-specific fluorescent dye. It has been found to be nontoxic when applied for short periods to a variety of cell types and has thus become an invaluable tool for examining mitochondrial morphology and ... More
UV dose-dependent caspase activation in a corneal epithelial cell line.
AuthorsShimmura S, Tadano K, Tsubota K
JournalCurr Eye Res
PubMed ID14972714
'PURPOSE: To characterize the UVB radiation-dependent patterns of caspase activation and cell death in SV 40 immortalized corneal epithelial cells. METHODS: Cell death in immortalized human corneal epithelial cells (T-HCEC) was induced by exposure to low (50 mJ/cm2) and high (450 mJ/cm2) doses of UVB. Cell death morphology was examined ... More
Mitochondria in tumor cells studied by laser scanning confocal microscopy.
AuthorsVilla AM, Doglia SM
JournalJ Biomed Opt
PubMed ID15065906
'We present here a confocal fluorescence microscopy study of mitochondria in sensitive and resistant carcinoma cells by using two potentiometric probes of mitochondria, rhodamine 123 (R123) and dimethylaminostyryl-methylpyridiniumiodine. We have found that active mitochondria in sensitive MCF-7 and multidrug resistant MCF-7/DX carcinoma cells are very different in localization and morphology. ... More
Reduction in the mitochondrial membrane potential of Toxoplasma gondii after invasion of host cells.
AuthorsTanabe K, Murakami K
JournalJ Cell Sci
PubMed ID6501438
'The membrane potential of Toxoplasma gondii, an obligatory intracellular protozoan parasite, was monitored with the cationic permeant fluorescent dye rhodamine 123 (R123). Fluorescence microscopy revealed R123 to be partitioned predominantly in a restricted part of the parasite, which consisted of twisted or branched tubules, or of granular bodies. These structures ... More
Glucose-induced oscillations in cytoplasmic free Ca2+ concentration precede oscillations in mitochondrial membrane potential in the pancreatic beta-cell.
AuthorsKindmark H, Köhler M, Brown G, Bränström R, Larsson O, Berggren PO
JournalJ Biol Chem
PubMed ID11445566
'Using dual excitation and fixed emission fluorescence microscopy, we were able to measure changes in cytoplasmic free Ca(2+) concentration ([Ca(2+)](i)) and mitochondrial membrane potential simultaneously in the pancreatic beta-cell. The beta-cells were exposed to a combination of the Ca(2+) indicator fura-2/AM and the indicator of mitochondrial membrane potential, rhodamine 123 ... More