Search results for " Mito"
showing 10 items of 895 documents
Pore-forming toxins activate MAPK p38 by causing loss of cellular potassium.
2009
Mitogen activated protein kinase (MAPK) p38 has emerged as a survival protein in cells that are attacked by bacterial toxins forming small membrane pores. Activation of p38 by pore forming toxins (PFT) has been attributed to osmotic stress, but here we show that loss of K+ is likely to be the critical parameter. Several lines of evidence support this conclusion: first, osmoprotection did not prevent p38-phosphorylation in alpha-toxin-loaded cells. Second, treatment of cells with a K+ ionophore, or simple incubation in K+-free medium sufficed to cause robust p38-phosphorylation. Third, media containing high [K+] prevented p38-activation by Staphylococcus aureus alpha-toxin, Vibrio cholerae c…
Procne e Filomela. Dal mito al simbolo letterario
2005
Una monografia sulla saga di Procne e Filomela da Omero a Ovidio, esaminata in primo luogo dal punto di vista mitografico, nello sviluppo delle diverse versioni del mito, quindi da quello metaletterario, in relazione alla metafora del poeta-usignolo e al suo percorso dalla letteratura greca arcaica alla letteratura latina di età augustea A monograph on the saga of Procne and Philomela from Homer to Ovid, surveyed first from a mythological point of view - taking into account the development of the myth's different versions -, then from a metaliterary one, following the path of the poet-nightingale metaphor from archaic Greek literature to augustan Latin literature.
Phylogenetic relationship among genera of Polymorphidae (Acanthocephala), inferred from nuclear and mitochondrial gene sequences.
2013
Abstract Acanthocephalans of the family Polymorphidae Meyer, 1931 are obligate endoparasites with complex life cycles. These worms use vertebrates (marine mammals, fish-eating birds and waterfowl) as definitive hosts and invertebrates (amphipods, decapods and euphausiids) as intermediate hosts to complete their life cycle. Polymorphidae has a wordwide distribution, containing 12 genera, with approximately 127 species. The family is diagnosed by having a spinose trunk, bulbose proboscis, double-walled proboscis receptacle, and usually four to eight tubular cement glands. To conduct a phylogenetic analysis, in the current study sequences of the small (18S) and large-subunit (28S) ribosomal RN…
Cytotoxicity and apoptosis induction by Fumaria officinalis extracts in leukemia and multiple myeloma cell lines
2021
Abstract Ethnopharmacological relevance Fumaria officinalis (Fumariaceae) is recorded in the Kurdish ethnobotany for various health problems. Aim of the study: In this study, the cytotoxic activity of F. officinalis extracts on two leukemia and nine multiple myeloma (MM) cell lines was investigated. Materials and methods: The cytotoxic and ferroptotic activity were examined by resazurin reduction assay. Flow cytometry, immunoblotting assay and fluorescence microscopy were used to measure cell cycle distribution, apoptosis, induction of reactive oxygen species (ROS), loss integrity of mitochondrial membrane potential (MMP) and autophagy. LC-ESI/MS was used to identify chemical constituents p…
Molecular mechanisms of rosmarinic acid from Salvia miltiorrhiza in acute lymphoblastic leukemia cells
2015
Abstract Ethnopharmacological relevance Rosmarinic acid (RA), a major hydrosoluble bioactive compound found in the Chinese medicinal herb, Salvia miltiorrhiza Bunge, which has been used in traditional Chinese medicine to treat various diseases, including cancer. However, the mechanisms have not been fully elucidated. Aim of the study Guided by microarray hybridization and Ingenuity Pathway Analysis, we identified modes of action of rosmarinic acid (RA) isolated from S. miltiorrhiza on acute lymphoblastic leukemia cells. Materials and methods Microarray data were verified by independent methods: Real-time RT-PCR (mRNA expression), resazurin assay (cytotoxicity of RA towards parental CCRF-CEM…
Cytotoxicity of 40 Egyptian plant extracts targeting mechanisms of drug-resistant cancer cells
2019
Abstract Background The multidrug resistance (MDR) phenotype encounters a major challenge to the success of established chemotherapy in cancer patients. We hypothesized that cytotoxic medicinal plants with novel phytochemicals can overcome MDR and kill MDR-cells with similar efficacy as drug sensitive cells. Purpose We evaluated plant extracts from an unexplored ecosystem in Egypt with unusual climate and nutrient conditions for their activity against sensitive and multidrug-resistant cancer cell lines. Material and methods/study design Methylene chloride: methanol (1:1) and methanol: H2O (7:3) extracts of 40 plants were prepared resulting in a sum of 76 fraction containing compounds with v…
GD3 ganglioside directly targets mitochondria in a bcl-2-controlled fashion.
2000
Lipid and glycolipid diffusible mediators are involved in the intracellular progression and amplification of apoptotic signals. GD3 ganglioside is rapidly synthesized from accumulated ceramide after the clustering of death-inducing receptors and triggers apoptosis. Here we show that GD3 induces dissipation of DeltaPsim and swelling of isolated mitochondria, which results in the mitochondrial release of cytochrome c, apoptosis inducing factor, and caspase 9. Soluble factors released from GD3-treated mitochondria are sufficient to trigger DNA fragmentation in isolated nuclei. All these effects can be blocked by cyclosporin A, suggesting that GD3 is acting at the level of the permeability tran…
DNA damage-induced cell death by apoptosis
2006
Following the induction of DNA damage, a prominent route of cell inactivation is apoptosis. During the last ten years, specific DNA lesions that trigger apoptosis have been identified. These include O6-methylguanine, base N-alkylations, bulky DNA adducts, DNA cross-links and DNA double-strand breaks (DSBs). Repair of these lesions are important in preventing apoptosis. An exception is O6-methylguanine-thymine lesions, which require mismatch repair for triggering apoptosis. Apoptosis induced by many chemical genotoxins is the consequence of blockage of DNA replication, which leads to collapse of replication forks and DSB formation. These DSBs are thought to be crucial downstream apoptosis-tr…
Deglycosylated bleomycin induces apoptosis in lymphoma cell via c-jun NH2-terminal kinase but not reactive oxygen species
2007
Bleomycin (BLM) has demonstrated potent activity in treating malignant lymphomas but its therapeutic efficacy is hampered by induction of lung fibrosis. This side effect is related to the ability of the drug to generate reactive oxygen species in lung cells. In the present study, we evaluated the consequences of deglycosylation of BLM in term of cytotoxic activity and generation of reactive oxygen species. When tested on U937 human lymphoma cells, both compounds generated a typical apoptotic phenotype. Cell death induction was associated with Bax oligomerization, dissipation of the mitochondrial membrane potential, release of cytochrome c, caspase activation, chromatin condensation and inte…
Characterization of cells with different mitochondrial membrane potential during apoptosis.
2005
Background Until now, the simultaneous analysis of several parameters during apoptosis, including DNA content and mitochondrial membrane potential (ΔΨ), has not been possible because of the spectral characteristics of the commonly used dyes. Using polychromatic flow cytometry based upon multiple laser and UV lamp excitation, we have characterized cells with different ΔΨ during apoptosis. Methods U937 cells were treated with the flavonoid quercetin (Qu) and stained with JC-1 to detect ΔΨ, propidium iodide (PI) for cell viability, Hoechst 33342 for DNA content, Annexin V conjugated with Alexa Fluor-647 for detection of phosphatidilserine (PS) exposure, marker of early apoptosis, or Mitotracke…