scholarly journals Establishing Irreversible Electroporation Electric Field Potential Threshold in A Suspension In Vitro Model for Cardiac and Neuronal Cells

2021 ◽  
Vol 10 (22) ◽  
pp. 5443
Author(s):  
Sahar Avazzadeh ◽  
Barry O’Brien ◽  
Ken Coffey ◽  
Martin O’Halloran ◽  
David Keane ◽  
...  
Keyword(s):  
Cell Death ◽  
Electric Field ◽  
Cell Viability ◽  
Cardiac Fibroblasts ◽  
Irreversible Electroporation ◽  
Field Potential ◽  
Optimal Threshold ◽  
Delayed Cell Death ◽  
Significant Difference

Aims: Irreversible electroporation is an ablation technique being adapted for the treatment of atrial fibrillation. Currently, there are many differences reported in the in vitro and pre-clinical literature for the effective voltage threshold for ablation. The aim of this study is a direct comparison of different cell types within the cardiovascular system and identification of optimal voltage thresholds for selective cell ablation. Methods: Monophasic voltage pulses were delivered in a cuvette suspension model. Cell viability and live–dead measurements of three different neuronal lines, cardiomyocytes, and cardiac fibroblasts were assessed under different voltage conditions. The immediate effects of voltage and the evolution of cell death was measured at three different time points post ablation. Results: All neuronal and atrial cardiomyocyte lines showed cell viability of less than 20% at an electric field of 1000 V/cm when at least 30 pulses were applied with no significant difference amongst them. In contrast, cardiac fibroblasts showed an optimal threshold at 1250 V/cm with a minimum of 50 pulses. Cell death overtime showed an immediate or delayed cell death with a proportion of cell membranes re-sealing after three hours but no significant difference was observed between treatments after 24 h. Conclusions: The present data suggest that understanding the optimal threshold of irreversible electroporation is vital for achieving a safe ablation modality without any side-effect in nearby cells. Moreover, the evolution of cell death post electroporation is key to obtaining a full understanding of the effects of IRE and selection of an optimal ablation threshold.

Inactivation of Salmonella Typhimurium in Orange Juice Containing Antimicrobial Agents by Pulsed Electric Field

2002 ◽  
Vol 65 (7) ◽  
pp. 1081-1087 ◽  
Author(s):  
ZIWEI LIANG ◽  
GAURI S. MITTAL ◽  
MANSEL W. GRIFFITHS
Keyword(s):  
Cell Death ◽  
Electric Field ◽  
Cell Viability ◽  
Salmonella Typhimurium ◽  
Orange Juice ◽  
Antimicrobial Agents ◽  
Ph Value ◽  
Pulsed Electric Field ◽  
Pulse Number ◽  
Significant Difference

Combinations of different hurdles, including moderately high temperatures (<60°C), antimicrobial compounds, and pulsed electric field (PEF) treatment, to reduce Salmonella in pasteurized and freshly squeezed orange juices (with and without pulp) were explored. Populations of Salmonella Typhimurium were found to decrease with an increase in pulse number and treatment temperature. At a field strength of 90 kV/cm, a pulse number of 20, and a temperature of 45°C, PEF treatment did not have a notable effect on cell viability or injury. At and above 46°C, however, cell death and injury were greatly increased. Salmonella numbers were reduced by 5.9 log cycles in freshly squeezed orange juice (without pulp) treated at 90 kV/cm, 50 pulses, and 55°C. When PEF treatment was carried out in the presence of nisin (100 U/ml of orange juice), lysozyme (2,400 U/ml), or a mixture of nisin (27.5 U/ml) and lysozyme (690 U/ml), cell viability loss was increased by an additional 0.04 to 2.75 log cycles. The combination of nisin and lysozyme had a more pronounced bactericidal effect than did either nisin or lysozyme alone. An additional Salmonella count reduction of at least 1.37 log cycles was achieved when the two antimicrobial agents were used in combination. No significant difference (P > 0.05) in cell death was attained by lowering the pH value; only cell injury increased. Inactivation by PEF was significantly more extensive (P < 0.05) in pasteurized orange juice than in freshly squeezed orange juice under the same treatment conditions. This increase might be due to the effect of the chemical composition of the juices.

scholarly journals First Description of the Generation of Human Schwann Cells Transfected With CRISPR Cas9 and a Model of Metformin Mitochondrial Metabolism in Metachromatic Leukodystrophy

2021 ◽  
Author(s):  
Nayibe Tatiana Sanchez Alvarez ◽  
Paula Katherine Bautista-Niño ◽  
Juanita Trejos-Suárez ◽  
Norma Cecilia Serrano-Díaz
Keyword(s):  
Cell Death ◽  
Cell Viability ◽  
Schwann Cells ◽  
Metachromatic Leukodystrophy ◽  
In Vitro Study ◽  
Basal Respiration ◽  
Ros Production ◽  
Transfected Cells ◽  
Significant Difference

Abstract Background: Metachromatic leukodystrophy (MLD) is a neurological lysosomal deposit disease that has an impact on public health despite its low incidence in the population. Existing treatments are expensive and inefficient. Few reports in the literature on pathophysiological events related to enzyme deficiency and subsequent accumulation of sulfatides; therefore, the use of metformin as an alternative treatment was evaluated in vitro to counteract the effects. Methodology: An experimental in vitro study that sought to determine the effect of the use of metformin on the accumulation of sulfates in glycolysis and mitochondrial function in an in vitro model of metachromatic leukodystrophy. Human Schwann cells (CSH) transfected with CRISPR Cas9 and without transfection were treated with different concentrations of sulfatides and metformin. Cell viability was evaluated by MTT and SYTOX Green; mitochondrial and glycolytic function by Seahorse XFe24, determination of reactive oxygen species (ROS) and cell death. Results: In the MTT trials, we found that treatment with different concentrations of sulfates did not affect cell viability. Transfected CSH showed higher cell death and ROS production when exposed to 100 µM sulfatides with a statistically significant difference (p <0.001), compared to nontransfected CSH cells. Sulfatides at concentrations of 10 to 100 µM affect mitochondrial bioenergetics as concentrations increase in transfected cells, in nontransfected cells they respond metabolically to exposure; Furthermore, transfected cells show a decrease in basal respiration and maximum respiration after being exposed to a concentration of 100 µM of sulphates; however, in double treatment of these cells with both sulfates and Metformin, respiration also decreases. Maximum and normal mitochondrial respiratory capacity. Conclusion: This research describes for the first time the generation of transfected CSH and the bioenergetic and mitochondrial effect of sulfates in Schwann cells, treatment with 500 µM of Metformin restores metabolic activity of these cells and decreases ROS production, as well as prevention of cell death.

Stew in its Own Juice: Protein Homeostasis Machinery Inhibition Reduces Cell Viability in Multiple Myeloma Cell Lines

2019 ◽  
Vol 19 (2) ◽  
pp. 112-119 ◽  
Author(s):  
Mariana B. de Oliveira ◽  
Luiz F.G. Sanson ◽  
Angela I.P. Eugenio ◽  
Rebecca S.S. Barbosa-Dantas ◽  
Gisele W.B. Colleoni
Keyword(s):  
Multiple Myeloma ◽  
Cell Death ◽  
Cell Viability ◽  
Cell Lines ◽  
Treatment Options ◽  
Compensatory Mechanism ◽  
Protein Homeostasis ◽  
Protein Response ◽  
Rpmi 8226

Introduction:Multiple myeloma (MM) cells accumulate in the bone marrow and produce enormous quantities of immunoglobulins, causing endoplasmatic reticulum stress and activation of protein handling machinery, such as heat shock protein response, autophagy and unfolded protein response (UPR).Methods:We evaluated cell lines viability after treatment with bortezomib (B) in combination with HSP70 (VER-15508) and autophagy (SBI-0206965) or UPR (STF- 083010) inhibitors.Results:For RPMI-8226, after 72 hours of treatment with B+VER+STF or B+VER+SBI, we observed 15% of viable cells, but treatment with B alone was better (90% of cell death). For U266, treatment with B+VER+STF or with B+VER+SBI for 72 hours resulted in 20% of cell viability and both treatments were better than treatment with B alone (40% of cell death). After both triplet combinations, RPMI-8226 and U266 presented the overexpression of XBP-1 UPR protein, suggesting that it is acting as a compensatory mechanism, in an attempt of the cell to handle the otherwise lethal large amount of immunoglobulin overload.Conclusion:Our in vitro results provide additional evidence that combinations of protein homeostasis inhibitors might be explored as treatment options for MM.

scholarly journals Pyrrolizidine Alkaloids Induce Cell Death in Human HepaRG Cells in a Structure-Dependent Manner

2020 ◽  
Vol 22 (1) ◽  
pp. 202
Author(s):  
Josephin Glück ◽  
Julia Waizenegger ◽  
Albert Braeuning ◽  
Stefanie Hessel-Pras
Keyword(s):  
Cell Death ◽  
Cell Viability ◽  
Pyrrolizidine Alkaloids ◽  
Defense Mechanism ◽  
Hepatoma Cell ◽  
Hepatoma Cell Line ◽  
Dependent Manner ◽  
Human Hepatoma Cell

Pyrrolizidine alkaloids (PAs) are a group of secondary metabolites produced in various plant species as a defense mechanism against herbivores. PAs consist of a necine base, which is esterified with one or two necine acids. Humans are exposed to PAs by consumption of contaminated food. PA intoxication in humans causes acute and chronic hepatotoxicity. It is considered that enzymatic PA toxification in hepatocytes is structure-dependent. In this study, we aimed to elucidate the induction of PA-induced cell death associated with apoptosis activation. Therefore, 22 structurally different PAs were analyzed concerning the disturbance of cell viability in the metabolically competent human hepatoma cell line HepaRG. The chosen PAs represent the main necine base structures and the different esterification types. Open-chained and cyclic heliotridine- and retronecine-type diesters induced strong cytotoxic effects, while treatment of HepaRG with monoesters did not affect cell viability. For more detailed investigation of apoptosis induction, comprising caspase activation and gene expression analysis, 14 PA representatives were selected. The proapoptotic effects were in line with the potency observed in cell viability studies. In vitro data point towards a strong structure–activity relationship whose effectiveness needs to be investigated in vivo and can then be the basis for a structure-associated risk assessment.

Increased cell death in osteopontin-deficient cardiac fibroblasts occurs by a caspase-3-independent pathway

2004 ◽  
Vol 287 (4) ◽  
pp. H1730-H1739 ◽  
Author(s):  
Ron Zohar ◽  
Baoqian Zhu ◽  
Peter Liu ◽  
Jaro Sodek ◽  
C. A. McCulloch
Keyword(s):  
Cell Death ◽  
Caspase 3 ◽  
Cardiac Fibroblasts ◽  
Chromatin Condensation ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Tunel Staining ◽  
Wild Type ◽  
Nuclear Fragmentation ◽  
A Cell

Reperfusion-induced oxidative injury to the myocardium promotes activation and proliferation of cardiac fibroblasts and repair by scar formation. Osteopontin (OPN) is a proinflammatory cytokine that is upregulated after reperfusion. To determine whether OPN enhances fibroblast survival after exposure to oxidants, cardiac fibroblasts from wild-type (WT) or OPN-null (OPN−/−) mice were treated in vitro with H2O2to model reperfusion injury. Within 1 h, membrane permeability to propidium iodide (PI) was increased from 5 to 60% in OPN−/−cells but was increased to only 20% in WT cells. In contrast, after 1–8 h of treatment with H2O2, the percent of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-stained cells was more than twofold higher in WT than OPN−/−cells. Electron microscopy of WT cells treated with H2O2showed chromatin condensation, nuclear fragmentation, and cytoplasmic and nuclear shrinkage, which are consistent with apoptosis. In contrast, H2O2-treated OPN−/−cardiac fibroblasts exhibited cell and nuclear swelling and membrane disruption that are indicative of cell necrosis. Treatment of OPN−/−and WT cells with a cell-permeable caspase-3 inhibitor reduced the percentage of TUNEL staining by more than fourfold in WT cells but decreased staining in OPN−/−cells by ∼30%. Although the percentage of PI-permeable WT cells was reduced threefold, the percent of PI-permeable OPN−/−cells was not altered. Restoration of OPN expression in OPN−/−fibroblasts reduced the percentage of PI-permeable cells but not TUNEL staining after H2O2treatment. Thus H2O2-induced cell death in OPN-deficient cardiac fibroblasts is mediated by a caspase-3-independent, necrotic pathway. We suggest that the increased expression of OPN in the myocardium after reperfusion may promote fibrosis by protecting cardiac fibroblasts from cell death.

Abstract 255: A Fibroblast Population Shares A Developmental Origin With Cardiovascular Lineages

2014 ◽  
Vol 115 (suppl_1) ◽  
Author(s):  
Sara Ranjbarvaziri ◽  
Shah Ali ◽  
Mahmood Talkhabi ◽  
Peng Zhao ◽  
Young-Jae Nam ◽  
...  
Keyword(s):  
Heart Development ◽  
Cardiac Fibroblasts ◽  
Immunohistochemical Analysis ◽  
Cell Types ◽  
Mouse Heart ◽  
Developmental Potential ◽  
Reporter Mice ◽  
Significant Difference ◽  
Definition Of

Rationale: The traditional definition of “cardiovascular” lineages describes the eponymous cell types - cardiomyoctes, endothelial cells, and smooth muscle cells - that arise from a common mesodermal progenitor cell during heart development. Fibroblasts are an abundant mesenchymal population in the mammalian heart which may have multiple, discrete developmental origins. Mesp1 represents the earliest marker of cardiovascular progenitors, contributing to the majority of cardiac lineages. To date no link between Mesp1 and fibroblast generation has been reported. Objective: We hypothesized progenitor cells expressing Mesp1 can also give rise to cardiac fibroblasts during heart development. Methods and Results: We generated Mesp1cre/+;R26RmTmG reporter mice where Cre-mediated recombination results in GFP activation in all Mesp1 expressing cells and their progeny. To explore their developmental potential, we isolated GFP+ cells from E7.5 Mesp1cre/+;R26RmTmG mouse. In vitro culture and transplantation studies into SCID mouse kidney capsule as wells as chick embryos showed fibroblastic adoption. Results showed that at E9.5 Mesp1+ and Mesp1- progenitors contributed to the proepicardium organ and later at E11.5 they formed epicardium. Analysis of adult hearts demonstrated that the majority of cardiac fibroblasts are derived from Mesp1 expressing cells. Immunohistochemical analysis of heart sections demonstrated expression of fibroblast markers (including DDR2, PDGFRα and Col1) in cells derived from both Mesp1+ and Mesp1- progenitors. Additionally, we investigated whether the two distinct fibroblast populations have different potency towards reprogramming to cardiomyocytes. Results showed no significant difference between Mesp1 and non-Mesp1 isolated fibroblasts to convert to cardiomyocyte fate. Conclusions: Our data demonstrates that cardiovascular progenitors expressing Mesp1 contribute to the proepicardium. These cells, as cardiovascular progenitors, also give rise to the highest portion of cardiac fibroblasts in the mouse heart.

scholarly journals Effects of acetylsalicylic acid and acetic acid solutions in VX2 carcinoma cells: In vitro analysis

2006 ◽  
Vol 21 (3) ◽  
pp. 151-154 ◽  
Author(s):  
Rogério Saad-Hossne ◽  
René Gamberini Prado ◽  
William Saad Hossne
Keyword(s):  
Cell Death ◽  
Acetic Acid ◽  
Cell Viability ◽  
Acetylsalicylic Acid ◽  
Neoplastic Cell ◽  
Carcinoma Cells ◽  
Acid Solutions ◽  
Vx2 Carcinoma ◽  
Vitro Analysis

PURPOSE: To analyze, in vitro, the effects of acetylsalicylic acid (aspirin) and acetic acid solutions on VX2 carcinoma cells in suspension and to examine the correlation between these effects and neoplastic cell death. METHODS: The VX2 tumor cells (10(7) cells/ml) were incubated in solutions containing differing concentrations (2.5% and 5%) of either acetylsalicylic acid or acetic acid, or in saline solution (controls). Every five minutes, cell viability was tested (using the trypan blue test) and analyzed under light microscopy. RESULTS: Tumor cell viability (in %) decreased progressively and, by 30 minutes, neoplastic cell death had occurred in all solutions. CONCLUSION: Based on this experimental model and the methodology employed, we conclude that these solutions cause neoplastic cell death in vitro.

scholarly journals Myocyte-Derived Hsp90 Modulates Collagen Upregulation via Biphasic Activation of STAT-3 in Fibroblasts during Cardiac Hypertrophy

2016 ◽  
Vol 37 (6) ◽  
Author(s):  
Ritwik Datta ◽  
Trisha Bansal ◽  
Santanu Rana ◽  
Kaberi Datta ◽  
Ratul Datta Chaudhuri ◽  
...  
Keyword(s):  
Cardiac Hypertrophy ◽  
Collagen Synthesis ◽  
Cardiac Fibroblasts ◽  
Heat Shock Protein 90 ◽  
Signaling Mechanism ◽  
Content Type ◽  
Collagen Expression ◽  
Significant Difference

ABSTRACT Signal transducer and activator of transcription 3 (STAT-3)-mediated signaling in relation to upregulated collagen expression in fibroblasts during cardiac hypertrophy is well defined. Our recent findings have identified heat shock protein 90 (Hsp90) to be a critical modulator of fibrotic signaling in cardiac fibroblasts in this disease milieu. The present study was therefore intended to analyze the role of Hsp90 in the STAT-3-mediated collagen upregulation process. Our data revealed a significant difference between in vivo and in vitro results, pointing to a possible involvement of myocyte-fibroblast cross talk in this process. Cardiomyocyte-targeted knockdown of Hsp90 in rats (Rattus norvegicus) in which the renal artery was ligated showed downregulated collagen synthesis. Furthermore, the results obtained with cardiac fibroblasts conditioned with Hsp90-inhibited hypertrophied myocyte supernatant pointed toward cardiomyocytes' role in the regulation of collagen expression in fibroblasts during hypertrophy. Our study also revealed a novel signaling mechanism where myocyte-derived Hsp90 orchestrates not only p65-mediated interleukin-6 (IL-6) synthesis but also its release in exosomal vesicles. Such myocyte-derived exosomes and myocyte-secreted IL-6 are responsible in unison for the biphasic activation of STAT-3 signaling in cardiac fibroblasts that culminates in excess collagen synthesis, leading to severely compromised cardiac function during cardiac hypertrophy.

Abstract 346: Lipophilic Statins Attenuate Human Atrial Fibroblast Viability In Vitro

2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Kiranjit K Sran ◽  
Yun Li ◽  
Saeid Ghavami ◽  
Melanie Ngo ◽  
Rakesh C Arora ◽  
...  
Keyword(s):  
Cell Death ◽  
Cell Viability ◽  
Heart Surgery ◽  
Cardiac Fibrosis ◽  
Therapeutic Option ◽  
Open Heart Surgery ◽  
Myocardial Cell ◽  
Dependent Manner ◽  
Vitro Effect

Cardiovascular diseases (CVD) leading to heart failure are associated with myocardial cell loss and cardiac fibrosis. Hydroxymethylglutaryl-Coenzyme-A Reductase (HMGR) inhibitors ("statins") are widely used to limit cardiovascular events in patients with hypercholesterolemia and CVD by altering their lipid profile. HMGR inhibition reduces cholesterol precursor L-mevalonate production, whose depletion induces autophagy, apoptosis, and endoplasmic reticulum stress in various cell types. However it is unclear if this is a class effect or a phenomenon specific to various compounds. We examined the in vitro effect of HMGR inhibition on human atrial fibroblast (hATF) viability with particular reference to hydrophilic vs lipophilic compounds. Hypothesis- Lipophilic statins induce cell death in primary hATF via mevalonate depletion; whereas hydrophilic statins do not have any effect on hATF viability. IRB approval was obtained for collection of hATF from consenting patients undergoing open heart surgery. Cells were treated with atorvastatin, simvastatin or pravastatin (0.1, 1.0 or 10 λM) for 24, 48, 72 or 96 hours. Expression of proteins involved in the regulation of apoptosis and autophagy was assessed using immunoblotting. Cell viability was assessed using MTT assay. Treatment of hATF with 0.1 - 10 λM atorvastatin or simvastatin (lipophilic statins) resulted in progressively reduced cell viability in time and dose-dependent manner. Viability could be rescued by coincubation with mevalonate. Expression of key apoptotic cascade proteins -Bcl2, Bax and cleaved Caspase3 showed a clear induction of apoptosis. Also, there was an increase in Atg5-12 expression at 24h indicating induction of early autophagic response. Pravastatin (hydrophilic statin) did not affect cell viability or autophagy and apoptosis. We conclude that statin-induced cell death is mediated by mevalonate depletion, which activates intrinsic apoptotic pathways in hATF. Lipophilic statins impair the viability of hATFs in vitro, whereas hydrophilic statins have no effect on cell growth and cell viability of hATFs. This may represent an additional pleiotropic effect of statins, and may represent a novel therapeutic option for the prevention and treatment of cardiac fibrosis.

scholarly journals TGF-β Promotes the Proliferation of Microglia In Vitro

2019 ◽  
Vol 10 (1) ◽  
pp. 20 ◽  
Author(s):  
Costansia Bureta ◽  
Takao Setoguchi ◽  
Yoshinobu Saitoh ◽  
Hiroyuki Tominaga ◽  
Shingo Maeda ◽  
...  
Keyword(s):  
Cell Death ◽  
Cell Lines ◽  
Transforming Growth Factor Beta ◽  
Microglial Cell ◽  
Transforming Growth Factor ◽  
Dependent Manner ◽  
In Vitro Proliferation ◽  
Inhibition Of Proliferation ◽  
Significant Difference

The activation and proliferation of microglia is characteristic of the early stages of brain pathologies. In this study, we aimed to identify a factor that promotes microglial activation and proliferation and examined the in vitro effects on these processes. We cultured microglial cell lines, EOC 2 and SIM-A9, with various growth factors and evaluated cell proliferation, death, and viability. The results showed that only transforming growth factor beta (TGF-β) caused an increase in the in vitro proliferation of both microglial cell lines. It has been reported that colony-stimulating factor 1 promotes the proliferation of microglia, while TGF-β promotes both proliferation and inhibition of cell death of microglia. However, upon comparing the most effective doses of both (assessed from the proliferation assay), we identified no statistically significant difference between the two factors in terms of cell death; thus, both have a proliferative effect on microglial cells. In addition, a TGF-β receptor 1 inhibitor, galunisertib, caused marked inhibition of proliferation in a dose-dependent manner, indicating that inhibition of TGF-β signalling reduces the proliferation of microglia. Therefore, galunisertib may represent a promising therapeutic agent for the treatment of neurodegenerative diseases via inhibition of nerve injury-induced microglial proliferation, which may result in reduced inflammatory and neuropathic and cancer pain.

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