CELL MEMBRANE AND CELL PERMEABILITY

The present study aimed to synthesize novel polycationic polymers composed of N-substituted L-2,3-diaminopropionic acid residues (DAPEGs) and investigate their cell permeability, cytotoxicity, and DNA-binding ability. The most efficient cell membrane-penetrating compounds (O2Oc-Dap(GO2)n-O2Oc-NH2, where n = 4, 6, and 8) showed dsDNA binding with a binding constant in the micromolar range (0.3, 3.4, and 0.19 µM, respectively) and were not cytotoxic to HB2 and MDA-MB-231 cells. Selected compounds used in the transfection of a GFP plasmid showed high transfection efficacy and minimal cytotoxicity. Their interaction with plasmid DNA and the increasing length of the main chain of tested compounds strongly influenced the organization and shape of the flower-like nanostructures formed, which were unique for 5/6-FAM-O2Oc-[Dap(GO2)]8-O2Oc-NH2 and typical for large proteins.

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Effect of a static magnetic field on the microscopic characteristics of highly efficient oil-removing bacteria

Water Science & Technology ◽

10.2166/wst.2017.530 ◽

2017 ◽

Vol 77 (2) ◽

pp. 296-303 ◽

Cited By ~ 1

Author(s):

Zhijun Ren ◽

Xiaodong Leng ◽

Qian Liu

Keyword(s):

Magnetic Field ◽

Magnetic Fields ◽

Cell Membrane ◽

Static Magnetic Field ◽

Cell Permeability ◽

Cell Membrane Permeability ◽

Oil Removal ◽

Low Intensity ◽

Highly Efficient ◽

Acinetobacter Sp

Abstract To better understand the microbial oil removal enhancement process by a magnetic field, the effect of a static magnetic field (SMF) on the microscopic characteristics of highly efficient biodegradation oil-removing bacteria was studied. The Acinetobacter sp. B11 strain with a 53.6% oil removal rate was selected as the reference bacteria. The changes in the microscopic characteristics of Acinetobacter sp. B11 such as the cell surface morphology, cell permeability and cell activity of the bacteria were investigated. The results showed that low-intensity magnetic fields (15–35 mT) improved the ability of Acinetobacter sp. B11 to remove oil by 11.9% at 25 mT compared with that of bacteria with no magnetic field. Without destroying the cell membrane, the low-intensity magnetic fields increased the cell membrane permeability and improved the activity of superoxide dismutase (SOD), which effectively enhanced the oil degradation performance of the bacteria.

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EFFECTS OF HERBICIDES OF DIFFERENT MODES OF ACTION ON LEAF-CELL MEMBRANE PERMEABILITY IN PHASEOLUS VULGARIS

Canadian Journal of Plant Science ◽

10.4141/cjps80-088 ◽

1980 ◽

Vol 60 (2) ◽

pp. 613-620 ◽

Cited By ~ 4

Author(s):

JACINTA CROWLEY ◽

G. N. PRENDEVILLE

Keyword(s):

Phaseolus Vulgaris ◽

Cell Membrane ◽

Membrane Permeability ◽

Leaf Damage ◽

Cell Permeability ◽

Cell Membrane Permeability ◽

Leaf Cell ◽

Visible Injury ◽

Modes Of Action ◽

2,4 Dichlorophenoxyacetic Acid

Leakage of electrolytes from leaf discs of treated Phaseolus vulgaris L. plants was used to study the effects of several herbicides of different modes of action on leaf-cell membrane permeability. Linuron (N-(3,4-dichlorophenyl)-N-methoxy-N-methylurea), prometryne (4,6-bisisopropylamino-2-methylthio-1,3,5-triazine), bromacil (5,bromo-6-methyl-3-(1-methyl-n-propyl) uracil), sodium azide and dalapon (2,2-dichloropropionic acid) increased leaf-cell permeability at 24 h after treatment and this occurred without appearance of leaf necrosis. Glyphosate (N-(phosphonomethyl) glycine) increased leaf-cell permeability at 96 h and this was always associated with visible injury, including wilting. Paraquat (1,1-dimethyl-4,4-bipyridylium) at 10−5M increased leaf-cell permeability 48 h after treatment, without apparent leaf damage, but at higher concentrations, increased permeability was always associated with visible effects. Chlorpropham (isopropyl N-(d)3-chlorophenyl) carbamate), picloram (4-amino-3,5,6-trichloropicolinic acid) and 2,4-D (2,4-dichlorophenoxyacetic acid) did not alter cell permeability even though epinastic symptoms in leaves became evident 24 h after treatment with picloram and 2,4-D.

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Effective inhibition of Clostridioides difficile by the novel peptide CM-A

PLoS ONE ◽

10.1371/journal.pone.0257431 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0257431

Author(s):

Sirirak Arthithanyaroj ◽

Surang Chankhamhaengdecha ◽

Urai Chaisri ◽

Ratchaneewan Aunpad ◽

Amornrat Aroonnual

Keyword(s):

Minimum Inhibitory Concentration ◽

Cell Membrane ◽

Inhibitory Concentration ◽

Cell Permeability ◽

Resistant Bacteria ◽

Microscopy Imaging ◽

Antibiotic Resistant ◽

Clostridioides Difficile ◽

Novel Approach ◽

Cell Depolarization

Clostridioides difficile infection is the most common cause of nosocomial and antibiotic-associated diarrhea. C. difficile treatment is increasingly likely to fail, and the recurrence rate is high. Antimicrobial peptides are considered an alternative treatment for many infectious diseases, including those caused by antibiotic resistant bacteria. In the present study, we identified a CM peptide, a hybrid of cecropin A and melittin, and its derivative which possesses potent antimicrobial activity against C. difficile strain 630. CM peptide exhibited antibacterial activity with minimum inhibitory concentration of 3.906 μg/ml (2.21 μM). A modified derivative of CM, CM-A, exhibited even greater activity with a minimum inhibitory concentration of 1.953 μg/ml (1.06 μM) and a minimum bactericidal concentration of 7.8125 μg/ml (4.24 μM), which indicates that CM-A peptide is more efficient than its parent peptide. A fluorescence-activated cell sorter analysis revealed that the membrane of C. difficile 630 could be an important target for CM-A. This peptide induced high levels of cell depolarization and cell permeability on C. difficile cell membrane. Moreover, electron microscopy imaging showed that CM-A interferes with the C. difficile cell membrane. Hence, the antimicrobial peptide CM-A may represent a promising novel approach for the treatment of C. difficile infections.

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EXTH-74. INCREASING CANCER CELL MEMBRANE PERMEABILITY THROUGH APPLICATION OF TUMOR TREATING FIELDS (TTFIELDS)

Neuro-Oncology ◽

10.1093/neuonc/noab196.713 ◽

2021 ◽

Vol 23 (Supplement_6) ◽

pp. vi180-vi180

Author(s):

Tali Voloshin ◽

Bella Koltun ◽

Lilach Koren ◽

Yaara Porat ◽

Alexandra Volodin ◽

...

Keyword(s):

Cell Membrane ◽

Membrane Permeability ◽

Cell Lines ◽

Cancer Cell ◽

Cell Permeability ◽

Cell Membrane Permeability ◽

Intracellular Accumulation ◽

Tumor Treating Fields ◽

Cell Counts ◽

Resistant Cells

Abstract INTRODUCTION Tumor Treating Fields (TTFields) are intermediate frequency, alternating electric fields with anti-mitotic effects on cancerous cells. TTFields are delivered non-invasively through arrays placed on the skin at the tumor region. TTFields therapy is approved in several territories for treatment of glioblastoma (GBM) and mesothelioma. Recently, TTFields have been shown to increase GBM cell membrane permeability. The current study aimed to explore this effect in multiple cell lines and examine the potential benefits of combining TTFields with other anticancer agents. METHODS TTFields were delivered to GBM (U-87 MG), uterine sarcoma (MES-SA), and breast adenocarcinoma (MCF-7) cell lines for 72hr across a range of frequencies (50-500kHz). Cytotoxicity of TTFields was examined by cell counts, and intracellular accumulation of 7-aminoactinomycin D (7-AAD) was measured by flow cytometry. Exposing the cells to 7-AAD at different time points relative to TTFields application cessation was used to determine the kinetics of cell membrane permeability. The potential of TTFields to facilitate intracellular accumulation of anthracycline chemotherapeutics was tested in chemotherapy-sensitive and chemotherapy-resistant cells. RESULTS Elevated intracellular accumulation of 7-AAD was observed in all examined cell lines treated with TTFields, at an optimal frequency that differed from that for maximal TTFields-induced cytotoxicity. No intracellular accumulation of 7-AAD was seen for measurements performed after termination of TTFields application, indicating that increased cell membrane permeability by TTFields was temporary and reversible. Lastly, the accumulation of chemotherapeutic agents in chemotherapy-resistant cancer cells was elevated to the same extent as in matched chemotherapy-sensitive cells when TTFields were delivered concomitant with chemotherapy. CONCLUSIONS TTFields increased cancer cell permeability in a transient and reversible manner across multiple cancer cell types. The increased permeability enhanced intracellular accumulation of chemotherapeutics, even within chemotherapy-resistant cells.

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Ernest Overton's Contribution to the Cell Membrane Concept: A Centennial Appreciation

Physiology ◽

10.1152/physiologyonline.1997.12.1.49 ◽

1997 ◽

Vol 12 (1) ◽

pp. 49-53 ◽

Cited By ~ 5

Author(s):

Arnost Kleinzeller

Keyword(s):

Cell Membrane ◽

Cell Membranes ◽

Structure And Function ◽

Cell Permeability ◽

Nerve Excitability ◽

And Function

In a series of three lectures in 1895-1899, Charles Ernest Overton (1865-1933) pioneered three fundamental concepts of the structure and function of cell membranes: 1) the lipid theory of cell permeability, 2) the lipid theory of narcosis, and 3) the involvement of an Na+/K+ exchange in muscle and nerve excitability.

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Powerful Antibacterial Peptides from Egg Albumin Hydrolysates

Antibiotics ◽

10.3390/antibiotics9120901 ◽

2020 ◽

Vol 9 (12) ◽

pp. 901

Author(s):

Abdul-Raouf Al-Mohammadi ◽

Ali Osman ◽

Gamal Enan ◽

Seham Abdel-Shafi ◽

Mona El-Nemer ◽

...

Keyword(s):

Cell Wall ◽

Antibacterial Activity ◽

Body Weight ◽

Cell Membrane ◽

Pathogenic Bacteria ◽

Klebsiella Oxytoca ◽

Ultra Performance Liquid Chromatography ◽

Cell Permeability ◽

Albino Rats ◽

Egg Albumin

Native egg albumin (NEA) was isolated from hen eggs and hydrolyzed by pepsin to produce hydrolyzed egg albumin (HEA). HEA was chemically characterized and screened for its antibacterial activity against 10 pathogenic bacteria (6 Gram (+) and 4 Gram (−)). The SDS-PAGE pattern of NEA showed molecular weights of hen egg albumin subunits ranging from 30 to 180 kDa. The highest intensive bands appeared at a molecular mass of about 50 and 97 kDa. Ultra-performance liquid chromatography (UPLC) of the peptic HEA revealed 44 peptides, 17 of them were dipeptides, and the other 27 fractions corresponded to bigger peptides (3–9 amino acids). The dipeptides and big peptides represented 26% and 74% of the total hydrolysate, respectively. The MIC of HEA was about 100 μg/L for Listeria monocytogenes, Bacillus cereus, Staphylococcus aureus, Salmonella typhimurium, Streptococcus pyogenes, and Klebsiella oxytoca and 150 μg/L for Pseudomonas aeruginosa, Bacillus subtilis, and Listeria ivanovii and 200 μg/L for Escherichia coli. L. monocytogenes was the most sensitive organism to HEA. Mixtures of HEA with antibiotics showed more significant antibacterial activity than individually using them. Transmission electron microscopy (TEM) revealed various signs of cellular deformation in the protein-treated bacteria. HEA may electrostatically and hydrophobically interact with the cell wall and cell membrane of the susceptible bacteria, engendering large pores and pore channels leading to cell wall and cell membrane disintegration. Higher cell permeability may, thus, occur, leading to cell emptiness, lysis, and finally death. Alternatively, no toxicity signs appeared when HEA was administrated to Wistar Albino rats as one single dose (2000, 5000 mg/kg body weight) or repeated daily dose (500 and 2500 mg/kg body weight/day) for 28 days to disclose the possible toxicity hazards. HEA did not produce any death.

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Statins and Voriconazole Induce Programmed Cell Death in Acanthamoeba castellanii

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00066-15 ◽

2015 ◽

Vol 59 (5) ◽

pp. 2817-2824 ◽

Cited By ~ 32

Author(s):

Carmen M. Martín-Navarro ◽

Atteneri López-Arencibia ◽

Ines Sifaoui ◽

María Reyes-Batlle ◽

Basilio Valladares ◽

...

Keyword(s):

Cell Death ◽

Programmed Cell Death ◽

Cell Membrane ◽

Acanthamoeba Castellanii ◽

Host Tissue ◽

Cell Permeability ◽

Caspase Activity ◽

Local Inflammation ◽

Content Type ◽

Life Threatening

ABSTRACTMembers of the genusAcanthamoebaare facultative pathogens of humans, causing a sight-threatening keratitis and a life-threatening encephalitis. In order to treat those infections properly, it is necessary to target the treatment not only to the trophozoite but also to the cyst. Furthermore, it may be advantageous to avoid parasite killing by necrosis, which may induce local inflammation. We must also avoid toxicity of host tissue. Many drugs which target eukaryotes are known to induce programmed cell death (PCD), but this process is poorly characterized inAcanthamoeba. Here, we study the processes of programmed cell death inAcanthamoeba, induced by several drugs, such as statins and voriconazole. We tested atorvastatin, fluvastatin, simvastatin, and voriconazole at the 50% inhibitory concentrations (IC50s) and IC90s that we have previously established. In order to evaluate this phenomenon, we investigated the DNA fragmentation, one of the main characteristics of PCD, with quantitative and qualitative techniques. Also, the changes related to phosphatidylserine exposure on the external cell membrane and cell permeability were studied. Finally, because caspases are key to PCD pathways, caspase activity was evaluated inAcanthamoeba. All the drugs assayed in this study induced PCD inAcanthamoeba. To the best of our knowledge, this is the first study where PCD induced by drugs is described quantitatively and qualitatively inAcanthamoeba.

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Changes in the Expression of Aquaporin-3 in the Gastrointestinal Tract Affect Drug Absorption

International Journal of Molecular Sciences ◽

10.3390/ijms20071559 ◽

2019 ◽

Vol 20 (7) ◽

pp. 1559 ◽

Cited By ~ 1

Author(s):

Nobutomo Ikarashi ◽

Chika Nagoya ◽

Risako Kon ◽

Satoshi Kitaoka ◽

Sayuri Kajiwara ◽

...

Keyword(s):

Cell Membrane ◽

Membrane Fluidity ◽

Water Transport ◽

Drug Absorption ◽

Control Level ◽

Cell Permeability ◽

Gi Tract ◽

Aquaporin 3 ◽

Cell Membrane Fluidity ◽

And Function

Aquaporin-3 (AQP3) plays an important role in water transport in the gastrointestinal (GI) tract. In this study, we conducted a Caco-2 cell permeability assay to examine how changes in the expression and function of AQP3 affect the rate at which a drug is absorbed via passive transport in the GI tract. When the function of AQP3 was inhibited by mercuric chloride or phloretin, there was no change in warfarin permeability. In contrast, when the expression of AQP3 protein was decreased by prostaglandin E2 (PGE2) treatment, warfarin permeability increased to approximately twice the control level, and membrane fluidity increased by 15%. In addition, warfarin permeability increased to an extent comparable to that after PGE2 treatment when cell membrane fluidity was increased by 10% via boric acid/EDTA treatment. These findings suggest the possibility that the increased drug absorption under decreased AQP3 expression was attributable to increased membrane fluidity. The results of this study demonstrate that the rate of water transport has little effect on drug absorption. However, our findings also indicate that although AQP3 and other similar transmembrane proteins do not themselves transport drugs, changes in their expression levels can cause changes in cell membrane fluidity, thus affecting drug absorption rates.

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Sarcolemmal permeability changes during early myocardial anoxia

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100084089 ◽

1978 ◽

Vol 36 (2) ◽

pp. 642-643

Author(s):

M. Ashraf ◽

L. Landa ◽

L. Nimmo ◽

C. M. Bloor

Keyword(s):

Cell Membrane ◽

Membrane Permeability ◽

Coronary Artery Occlusion ◽

Artery Occlusion ◽

Cell Membrane Permeability ◽

Enzyme Release ◽

Sprague Dawley ◽

Sprague Dawley Rats ◽

Sarcolemmal Permeability ◽

Membrane Changes

Following coronary artery occlusion, the myocardial cells lose intracellular enzymes that appear in the serum 3 hrs later. By this time the cells in the ischemic zone have already undergone irreversible changes, and the cell membrane permeability is variably altered in the ischemic cells. At certain stages or intervals the cell membrane changes, allowing release of cytoplasmic enzymes. To correlate the changes in cell membrane permeability with the enzyme release, we used colloidal lanthanum (La+++) as a histological permeability marker in the isolated perfused hearts. The hearts removed from sprague-Dawley rats were perfused with standard Krebs-Henseleit medium gassed with 95% O2 + 5% CO2. The hypoxic medium contained mannitol instead of dextrose and was bubbled with 95% N2 + 5% CO2. The final osmolarity of the medium was 295 M osmol, pH 7. 4.

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