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Agnass P, Rodermond HM, van Veldhuisen E, Vogel JA, Ten Cate R, van Lienden KP, van Gulik TM, Franken NAP, Oei AL, Kok HP, Besselink MG, Crezee J. Quantitative analysis of contribution of mild and moderate hyperthermia to thermal ablation and sensitization of irreversible electroporation of pancreatic cancer cells. J Therm Biol 2023; 115:103619. [PMID: 37437370 DOI: 10.1016/j.jtherbio.2023.103619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 05/09/2023] [Accepted: 05/30/2023] [Indexed: 07/14/2023]
Abstract
INTRODUCTION Irreversible electroporation (IRE) is an ablation modality that applies short, high-voltage electric pulses to unresectable cancers. Although considered a non-thermal technique, temperatures do increase during IRE. This temperature rise sensitizes tumor cells for electroporation as well as inducing partial direct thermal ablation. AIM To evaluate the extent to which mild and moderate hyperthermia enhance electroporation effects, and to establish and validate in a pilot study cell viability models (CVM) as function of both electroporation parameters and temperature in a relevant pancreatic cancer cell line. METHODS Several IRE-protocols were applied at different well-controlled temperature levels (37 °C ≤ T ≤ 46 °C) to evaluate temperature dependent cell viability at enhanced temperatures in comparison to cell viability at T = 37 °C. A realistic sigmoid CVM function was used based on thermal damage probability with Arrhenius Equation and cumulative equivalent minutes at 43 °C (CEM43°C) as arguments, and fitted to the experimental data using "Non-linear-least-squares"-analysis. RESULTS Mild (40 °C) and moderate (46 °C) hyperthermic temperatures boosted cell ablation with up to 30% and 95%, respectively, mainly around the IRE threshold Eth,50% electric-field strength that results in 50% cell viability. The CVM was successfully fitted to the experimental data. CONCLUSION Both mild- and moderate hyperthermia significantly boost the electroporation effect at electric-field strengths neighboring Eth,50%. Inclusion of temperature in the newly developed CVM correctly predicted both temperature-dependent cell viability and thermal ablation for pancreatic cancer cells exposed to a relevant range of electric-field strengths/pulse parameters and mild moderate hyperthermic temperatures.
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Affiliation(s)
- P Agnass
- Amsterdam UMC Location University of Amsterdam, Radiation Oncology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Surgery, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Oncology and Radiobiology, Meibergdreef 9, Amsterdam, the Netherlands.
| | - H M Rodermond
- Amsterdam UMC Location University of Amsterdam, Radiation Oncology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Oncology and Radiobiology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Molecular Medicine, Meibergdreef 9, Amsterdam, the Netherlands.
| | - E van Veldhuisen
- Amsterdam UMC Location University of Amsterdam, Surgery, Meibergdreef 9, Amsterdam, the Netherlands.
| | - J A Vogel
- Amsterdam UMC Location University of Amsterdam, Gastroenterology & Hepatology, Meibergdreef 9, Amsterdam, the Netherlands.
| | - R Ten Cate
- Amsterdam UMC Location University of Amsterdam, Radiation Oncology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Oncology and Radiobiology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Molecular Medicine, Meibergdreef 9, Amsterdam, the Netherlands.
| | - K P van Lienden
- Department of Intervention Radiology, St. Antonius Hospital, Nieuwegein, the Netherlands.
| | - T M van Gulik
- Amsterdam UMC Location University of Amsterdam, Surgery, Meibergdreef 9, Amsterdam, the Netherlands.
| | - N A P Franken
- Amsterdam UMC Location University of Amsterdam, Radiation Oncology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Oncology and Radiobiology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Molecular Medicine, Meibergdreef 9, Amsterdam, the Netherlands.
| | - A L Oei
- Amsterdam UMC Location University of Amsterdam, Radiation Oncology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Oncology and Radiobiology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam UMC Location University of Amsterdam, Experimental Molecular Medicine, Meibergdreef 9, Amsterdam, the Netherlands.
| | - H P Kok
- Amsterdam UMC Location University of Amsterdam, Radiation Oncology, Meibergdreef 9, Amsterdam, the Netherlands; Cancer Center Amsterdam, Treatment and Quality of Life, Cancer Biology and Immunology, Amsterdam, the Netherlands.
| | - M G Besselink
- Amsterdam UMC Location University of Amsterdam, Surgery, Meibergdreef 9, Amsterdam, the Netherlands.
| | - J Crezee
- Amsterdam UMC Location University of Amsterdam, Radiation Oncology, Meibergdreef 9, Amsterdam, the Netherlands; Cancer Center Amsterdam, Treatment and Quality of Life, Cancer Biology and Immunology, Amsterdam, the Netherlands.
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Lv Y, Liu H, Feng Z, Zhang J, Chen G, Yao C. The Enlargement of Ablation Area by Electrolytic Irreversible Electroporation (E-IRE) Using Pulsed Field with Bias DC Field. Ann Biomed Eng 2022; 50:1964-1973. [PMID: 35852648 DOI: 10.1007/s10439-022-03017-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 07/07/2022] [Indexed: 12/30/2022]
Abstract
Irreversible electroporation (IRE) by high-strength electric pulses is a biomedical technique that has been effectively used for minimally invasive tumor therapy while maintaining the functionality of adjacent important tissues, such as blood vessels and nerves. In general, pulse delivery using needle electrodes can create a reversible electroporation region beyond both the ablation area and the vicinity of the needle electrodes, limiting enlargement of the ablation area. Electrochemical therapy (EChT) can also be used to ablate a tumor near electrodes by electrolysis using a direct field with a constant current or voltage (DC field). Recently, reversible electroporated cells have been shown to be susceptible to electrolysis at relatively low doses. Reversible electroporation can also be combined with electrolysis for tissue ablation. Therefore, the objective of this study is to use electrolysis to remove the reversible electroporation area and thereby enlarge the ablation area in potato slices in vitro using a pulsed field with a bias DC field (constant voltage). We call this protocol electrolytic irreversible electroporation (E-IRE). The area over which the electrolytic effect induced a pH change was also measured. The results show that decreasing the pulse frequency using IRE alone is found to enlarge the ablation area. The ablation area generated by E-IRE is significantly larger than that generated by using IRE or EChT alone. The ablation area generated by E-IRE at 1 Hz is 109.5% larger than that generated by IRE, showing that the reversible electroporation region is transformed into an ablation region by electrolysis. The area with a pH change produced by E-IRE is larger than that produced by EChT alone. Decreasing the pulse frequency in the E-IRE protocol can further enlarge the ablation area. The results of this study are a preliminary indication that the E-IRE protocol can effectively enlarge the ablation area and enhance the efficacy of traditional IRE for use in ablating large tumors.
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Affiliation(s)
- Yanpeng Lv
- School of Electrical Engineering, Zhengzhou University, Zhengzhou, 450001, China.
| | - Heqing Liu
- School of Electrical Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Zhikui Feng
- School of Electrical Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Jianhua Zhang
- School of Electrical Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Genyong Chen
- School of Electrical Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Chenguo Yao
- School of Electrical Engineering, Chongqing University, Chongqing, 400030, China
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Hadinia N, Edalatian Dovom MR, Yavarmanesh M. The effect of fermentation conditions (temperature, salt concentration, and pH) with lactobacillus strains for producing Short Chain Fatty Acids. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113709] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Kania K, Levytska A, Drożak A, Andrzej B, Paweł D, Zienkiewicz M. The effect of temperature conditions during growth on the transformation frequency of Coccomyxa subellipsoidea C-169 obtained by electroporation. Biochem Biophys Rep 2022; 30:101220. [PMID: 35198739 PMCID: PMC8844808 DOI: 10.1016/j.bbrep.2022.101220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 12/27/2021] [Accepted: 01/22/2022] [Indexed: 10/26/2022] Open
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Abdalla T, Al-Rumaithi H, Osaili TM, Hasan F, Obaid RS, Abushelaibi A, Ayyash MM. Prevalence, Antibiotic-Resistance, and Growth Profile of Vibrio spp. Isolated From Fish and Shellfish in Subtropical-Arid Area. Front Microbiol 2022; 13:861547. [PMID: 35464960 PMCID: PMC9019552 DOI: 10.3389/fmicb.2022.861547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 03/18/2022] [Indexed: 12/03/2022] Open
Abstract
The study aimed to determine the prevalence of different species of Vibrio spp. in fish and shellfish sold in subtropical-arid countries (United Arab Emirates). It also examined the antimicrobial resistance of the isolated species and their growth behavior upon in vitro environmental changes concerning temperature, pH, and salinity. The prevalence of Vibrio spp. in fish and shellfish samples, was 64.5 and 92%, respectively. However, Vibrio parahemolyticus were detected in a mere 7.5 and 13.0% of the samples, respectively. On the other hand, Vibrio mimicus was detected in 1.5 and 8.5% of the samples, respectively. None of the six antibiotics studied except for Sulfamethoxazole-trimethoprim were effective against fish Vibrio spp. isolates. On a similar note, three antibiotics, namely Penicillin, Daptomycin, and Vancomycin, were ineffective against the shellfish isolates. The growth of the microorganisms did not show any significant trend with changes in pH and salinity. The optimum temperature for Vibrio spp. growth was observed to be 37°C.
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Affiliation(s)
- Tarfa Abdalla
- Department of Food Science, College of Agriculture and Veterinary Medicine, United Arab Emirates University (UAEU), Al Ain, United Arab Emirates
| | - Hind Al-Rumaithi
- Department of Food Science, College of Agriculture and Veterinary Medicine, United Arab Emirates University (UAEU), Al Ain, United Arab Emirates
| | - Tareq M Osaili
- Department of Clinical Nutrition and Dietetics, College of Health Sciences, University of Sharjah, Sharjah, United Arab Emirates.,Sharjah Institute for Medical Research, University of Sharjah, Sharjah, United Arab Emirates.,Department of Nutrition and Food Technology, Faculty of Agriculture, Jordan University of Science and Technology, Irbid, Jordan
| | - Fayeza Hasan
- Sharjah Institute for Medical Research, University of Sharjah, Sharjah, United Arab Emirates
| | - Reyad S Obaid
- Department of Clinical Nutrition and Dietetics, College of Health Sciences, University of Sharjah, Sharjah, United Arab Emirates
| | - Aisha Abushelaibi
- Campus Director at Higher Colleges of Technology, Dubai, United Arab Emirates
| | - Mutamed M Ayyash
- Department of Food Science, College of Agriculture and Veterinary Medicine, United Arab Emirates University (UAEU), Al Ain, United Arab Emirates
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Abstract
In-cell structural biology aims at extracting structural information about proteins or nucleic acids in their native, cellular environment. This emerging field holds great promise and is already providing new facts and outlooks of interest at both fundamental and applied levels. NMR spectroscopy has important contributions on this stage: It brings information on a broad variety of nuclei at the atomic scale, which ensures its great versatility and uniqueness. Here, we detail the methods, the fundamental knowledge, and the applications in biomedical engineering related to in-cell structural biology by NMR. We finally propose a brief overview of the main other techniques in the field (EPR, smFRET, cryo-ET, etc.) to draw some advisable developments for in-cell NMR. In the era of large-scale screenings and deep learning, both accurate and qualitative experimental evidence are as essential as ever to understand the interior life of cells. In-cell structural biology by NMR spectroscopy can generate such a knowledge, and it does so at the atomic scale. This review is meant to deliver comprehensive but accessible information, with advanced technical details and reflections on the methods, the nature of the results, and the future of the field.
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Affiliation(s)
- Francois-Xavier Theillet
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
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Agostini F, Vicinanza C, Biolo G, Spessotto P, Da Ros F, Lombardi E, Durante C, Mazzucato M. Nucleofection of Adipose Mesenchymal Stem/Stromal Cells: Improved Transfection Efficiency for GMP Grade Applications. Cells 2021; 10:cells10123412. [PMID: 34943920 PMCID: PMC8700287 DOI: 10.3390/cells10123412] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/26/2021] [Accepted: 12/02/2021] [Indexed: 12/19/2022] Open
Abstract
Nucleofection (NF) is a safe, non-viral transfection method, compatible with Good Manufacturing Practice guidelines. Such a technique is useful to improve therapeutic effectiveness of adipose tissue mesenchymal stem cells (ASC) in clinical settings, but improvement of NF efficiency is mandatory. Supernatant rich in growth factors (SRGF) is a clinical-grade medium additive for ASC expansion. We showed a dramatically increased NF efficiency and post-transfection viability in ASC expanded in presence of SRGF (vs. fetal bovine serum). SRGF expanded ASC were characterized by increased vesicle endocytosis but lower phagocytosis properties. SRGF increased n-6/n-3 ratio, reduced membrane lipid raft occurrence, and lowered intracellular actin content in ASC. A statistical correlation between NF efficiency and lipid raft availability on cell membranes was shown, even though a direct relationship could not be demonstrated: attempts to selectively modulate lipid rafts levels were, in fact, limited by technical constraints. In conclusion, we reported for the first time that tuning clinical-grade compatible cell culture conditions can significantly improve ASC transfection efficiency by a non-viral and safe approach. A deep mechanistic characterization is extremely complex, but we can hypothesize that integrated changes in membrane structure and intracellular actin content could contribute to explain SRGF impact on ASC NF efficiency.
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Affiliation(s)
- Francesco Agostini
- Stem Cell Unit, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, Via F. Gallini 2, 33081 Aviano, Italy; (C.V.); (F.D.R.); (E.L.); (C.D.); (M.M.)
- Correspondence: ; Tel.: +39-0434-659095
| | - Carla Vicinanza
- Stem Cell Unit, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, Via F. Gallini 2, 33081 Aviano, Italy; (C.V.); (F.D.R.); (E.L.); (C.D.); (M.M.)
| | - Gianni Biolo
- Unit of Internal Medicine, Clinica Medica, Department of Medical Surgical and Health Sciences, University of Trieste, Strada di Fiume 447, 34100 Trieste, Italy;
| | - Paola Spessotto
- Division of Molecular Oncology, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, Via F. Gallini 2, 33081 Aviano, Italy;
| | - Francesco Da Ros
- Stem Cell Unit, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, Via F. Gallini 2, 33081 Aviano, Italy; (C.V.); (F.D.R.); (E.L.); (C.D.); (M.M.)
| | - Elisabetta Lombardi
- Stem Cell Unit, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, Via F. Gallini 2, 33081 Aviano, Italy; (C.V.); (F.D.R.); (E.L.); (C.D.); (M.M.)
| | - Cristina Durante
- Stem Cell Unit, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, Via F. Gallini 2, 33081 Aviano, Italy; (C.V.); (F.D.R.); (E.L.); (C.D.); (M.M.)
| | - Mario Mazzucato
- Stem Cell Unit, Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, Via F. Gallini 2, 33081 Aviano, Italy; (C.V.); (F.D.R.); (E.L.); (C.D.); (M.M.)
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8
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Wu S, Xu X, Yang N, Jin Y, Jin Z, Xie Z. Inactivation of Escherichia coli O157:H7 in apple juice via induced electric field (IEF) and its bactericidal mechanism. Food Microbiol 2021; 102:103928. [PMID: 34809954 DOI: 10.1016/j.fm.2021.103928] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 10/23/2021] [Accepted: 10/25/2021] [Indexed: 12/28/2022]
Abstract
Non-conventional heating technology based on electric fields can be utilized to process liquid foods. In this study, the induced electric field (IEF) was investigated to clarify its inactivation mechanism on E.coli. Staining results show that inactivation of E.coli by IEF can be attributed to the reversible destruction of the cell membrane, followed by the denaturation of intracellular enzymes, and finally the irreversible rupture of the cell membrane. The increased levels of extracellular proteins and nucleic acids were also observed. IEF treatment at 400 Hz and 800 V (or 53 V/cm) results in a reduction of 4.5 log CFU·mL-1 in the number of E.coli. Storage life analysis shows that IEF treatment can improve the stability of apple juice and the content of bioactive components. Thus, IEF is a potential technique for liquid food processing.
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Affiliation(s)
- Shilin Wu
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, PR China; School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, PR China
| | - Xueming Xu
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, PR China; School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, PR China; International Joint Laboratory on Food Safety, Synergetie Innovation Center of Food Satety and Nutrition, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, PR China
| | - Na Yang
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, PR China; School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, PR China; State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academic of Sciences, Jinan, 250301, PR China; South China Agricultural University, Guangzhou, 510642, PR China.
| | - Yamei Jin
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, PR China; School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, PR China
| | - Zhengyu Jin
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, PR China; School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, PR China
| | - Zhengjun Xie
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, PR China; School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, PR China
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Edelblute C, Mangiamele C, Heller R. Moderate Heat-Assisted Gene Electrotransfer as a Potential Delivery Approach for Protein Replacement Therapy through the Skin. Pharmaceutics 2021; 13:pharmaceutics13111908. [PMID: 34834323 PMCID: PMC8624362 DOI: 10.3390/pharmaceutics13111908] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 10/20/2021] [Accepted: 11/06/2021] [Indexed: 11/28/2022] Open
Abstract
Gene-based approaches for protein replacement therapies have the potential to reduce the number of administrations. Our previous work demonstrated that expression could be enhanced and/or the applied voltage reduced by preheating the tissue prior to pulse administration. In the current study, we utilized our 16-pin multi-electrode array (MEA) and incorporated nine optical fibers, connected to an infrared laser, between each set of four electrodes to heat the tissue to 43 °C. For proof of principle, a guinea pig model was used to test delivery of reporter genes. We observed that when the skin was preheated, it was possible to achieve the same expression levels as gene electrotransfer without preheating, but with a 23% reduction of applied voltage or a 50% reduction of pulse number. With respect to expression distribution, preheating allowed for delivery to the deep dermis and muscle. This suggested that this cutaneous delivery approach has the potential to achieve expression in the systemic circulation, thus this protocol was repeated using a plasmid encoding Human Factor IX. Elevated Factor IX serum protein levels were detected by ELISA up to 100 days post gene delivery. Further work will involve optimizing protein levels and scalability in an effort to reduce application frequency.
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Affiliation(s)
- Chelsea Edelblute
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, 4211 Monarch Way, Suite 300, Norfolk, VA 23508, USA; (C.E.); (C.M.)
- Department of Biomedical Sciences, Graduate School, Old Dominion University, Norfolk, VA 23508, USA
| | - Cathryn Mangiamele
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, 4211 Monarch Way, Suite 300, Norfolk, VA 23508, USA; (C.E.); (C.M.)
| | - Richard Heller
- Department of Medical Engineering, Colleges of Medicine and Engineering, University of South Florida, Tampa, FL 33612, USA
- Correspondence:
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Peled E, Sosnik A. Amphiphilic galactomannan nanoparticles trigger the alternative activation of murine macrophages. J Control Release 2021; 339:473-483. [PMID: 34662585 DOI: 10.1016/j.jconrel.2021.10.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 08/12/2021] [Accepted: 10/13/2021] [Indexed: 12/24/2022]
Abstract
Macrophages are highly plastic phagocytic cells that can exist in distinct phenotypes and play key roles in physiological and pathological pathways. They can be classically activated to the pro-inflammatory M1 phenotype or alternatively activated to an M2 anti-inflammatory one by various stimuli in the biological milieu. Different biomaterials polarize macrophages to M1 or M2 phenotypes and emerged as a very promising strategy to modulate their activation and performance. In this work, we investigate the ability of drug-free amphiphilic nanoparticles (hydrodynamic diameter of ~130 nm) produced by the self-assembly of a graft copolymer of hydrolyzed galactomannan, a natural polysaccharide of galactose and mannose, that was hydrophobized in the side-chain with poly(methyl methacrylate) blocks and that can encapsulate hydrophobic drugs, to trigger macrophage polarization. The compatibility and uptake of the nanoparticles are demonstrated in the murine macrophage cell line RAW264.7 by a metabolic assay, confocal laser scanning fluorescence microscopy (CLSFM) and imaging flow cytometry in the absence and the presence of endocytosis inhibitors. Results indicate that they are internalized by both clathrin- and caveolin-mediated endocytosis. The ability of these drug-free nanoparticles to polarize these cells to the M2-like phenotype and to switch an M1 to an M2 phenotype is confirmed by the downregulation of the M1 marker cluster of differentiation 80 (CD80), and upregulation of M2 markers CD163 and CD206, as measured by flow cytometry and CLSFM. In addition, we preliminarily assess the effect of the nanoparticles on wound healing by tracking the closure of an artificial wound of RAW264.7 macrophages in a scratch assay. Findings indicate a faster closure of the wound in the presence of the nanoparticles with respect to untreated cells. Finally, a migration assay utilizing a macrophage/fibroblast co-culture model in vitro demonstrates that M2 polarization increases fibroblast migration by 24-fold with respect to untreated cells. These findings demonstrate the ability of this nanotechnology platform to interfere and change the macrophages phenotype in vitro and represent robust evidence for the investigation of their therapeutic performance alone or in combination with an encapsulated hydrophobic drug in wound models in vivo.
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Affiliation(s)
- Ella Peled
- Laboratory of Pharmaceutical Nanomaterials Science, Faculty of Materials Science and Engineering, Technion-Israel Institute of Technology, 3200003 Haifa, Israel
| | - Alejandro Sosnik
- Laboratory of Pharmaceutical Nanomaterials Science, Faculty of Materials Science and Engineering, Technion-Israel Institute of Technology, 3200003 Haifa, Israel.
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11
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Jenkins EPW, Finch A, Gerigk M, Triantis IF, Watts C, Malliaras GG. Electrotherapies for Glioblastoma. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2100978. [PMID: 34292672 PMCID: PMC8456216 DOI: 10.1002/advs.202100978] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 05/20/2021] [Indexed: 05/08/2023]
Abstract
Non-thermal, intermediate frequency (100-500 kHz) electrotherapies present a unique therapeutic strategy to treat malignant neoplasms. Here, pulsed electric fields (PEFs) which induce reversible or irreversible electroporation (IRE) and tumour-treating fields (TTFs) are reviewed highlighting the foundations, advances, and considerations of each method when applied to glioblastoma (GBM). Several biological aspects of GBM that contribute to treatment complexity (heterogeneity, recurrence, resistance, and blood-brain barrier(BBB)) and electrophysiological traits which are suggested to promote glioma progression are described. Particularly, the biological responses at the cellular and molecular level to specific parameters of the electrical stimuli are discussed offering ways to compare these parameters despite the lack of a universally adopted physical description. Reviewing the literature, a disconnect is found between electrotherapy techniques and how they target the biological complexities of GBM that make treatment difficult in the first place. An attempt is made to bridge the interdisciplinary gap by mapping biological characteristics to different methods of electrotherapy, suggesting important future research topics and directions in both understanding and treating GBM. To the authors' knowledge, this is the first paper that attempts an in-tandem assessment of the biological effects of different aspects of intermediate frequency electrotherapy methods, thus offering possible strategies toward GBM treatment.
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Affiliation(s)
- Elise P. W. Jenkins
- Division of Electrical EngineeringDepartment of EngineeringUniversity of CambridgeCambridgeCB3 0FAUK
| | - Alina Finch
- Institute of Cancer and Genomic ScienceUniversity of BirminghamBirminghamB15 2TTUK
| | - Magda Gerigk
- Division of Electrical EngineeringDepartment of EngineeringUniversity of CambridgeCambridgeCB3 0FAUK
| | - Iasonas F. Triantis
- Department of Electrical and Electronic EngineeringCity, University of LondonLondonEC1V 0HBUK
| | - Colin Watts
- Institute of Cancer and Genomic ScienceUniversity of BirminghamBirminghamB15 2TTUK
| | - George G. Malliaras
- Division of Electrical EngineeringDepartment of EngineeringUniversity of CambridgeCambridgeCB3 0FAUK
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Li SY, Duan CQ, Han ZH. Grape polysaccharides: compositional changes in grapes and wines, possible effects on wine organoleptic properties, and practical control during winemaking. Crit Rev Food Sci Nutr 2021; 63:1119-1142. [PMID: 34342521 DOI: 10.1080/10408398.2021.1960476] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Polysaccharides present in grapes interact with wine sensory-active compounds (polyphenols and volatile compounds) via different mechanisms and can affect wine organoleptic qualities such as astringency, color and aroma. Studies on the role that grape polysaccharides play in wines are reviewed in this paper. First, the composition of grape polysaccharides and their changes during grape ripening, winemaking and aging are introduced. Second, different interaction mechanisms of grape polysaccharides and wine sensory-active compounds (flavanols, anthocyanins and volatiles) are introduced, and the possible effects on wine astringency, color and aroma caused by these interactions are illustrated. Finally, the control of the grape polysaccharide content in practice is discussed, including classical winemaking methods (applying different maceration enzymes, temperature control, co-fermentation, blending), modern vinification technologies (pulsed electric field, ultrasound treatment), and the development of new grape polysaccharide products.
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Affiliation(s)
- Si-Yu Li
- Ministry of Agriculture, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Beijing, China.,College of Horticulture, China Agricultural University, Beijing, China.,Center for Viticulture & Enology, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.,Ministry of Agriculture and Rural Affairs, Key Laboratory of Viticulture and Enology, Beijing, China
| | - Chang-Qing Duan
- Center for Viticulture & Enology, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.,Ministry of Agriculture and Rural Affairs, Key Laboratory of Viticulture and Enology, Beijing, China
| | - Zhen-Hai Han
- Ministry of Agriculture, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Nutrition and Physiology), Beijing, China.,College of Horticulture, China Agricultural University, Beijing, China
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13
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Chang X, Zha L, Wallimann A, Mohsen MO, Krenger P, Liu X, Vogel M, Bachmann MF. Low-affinity but high-avidity interactions may offer an explanation for IgE-mediated allergen cross-reactivity. Allergy 2021; 76:2565-2574. [PMID: 33866583 PMCID: PMC8361967 DOI: 10.1111/all.14864] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 02/23/2021] [Accepted: 03/14/2021] [Indexed: 12/04/2022]
Abstract
Background Allergy is a global disease with overall frequencies of >20%. Symptoms vary from irritating local itching to life‐threatening systemic anaphylaxis. Even though allergies are allergen‐specific, there is a wide range of cross‐reactivities (eg apple and latex) that remain largely unexplained. Given the abilities of low‐affinity IgG antibodies to inhibit mast cells activation, here we elucidate the minimal affinity of IgE antibodies to induce type I hypersensitivity. Methods Three mature (high‐affinity) IgE antibodies recognizing three distinct epitopes on Fel d 1, the major cat allergen, were back‐mutated to germline conformation, resulting in binding to Fel d 1 with low affinity. The ability of these IgE antibodies to activate mast cells in vitro and in vivo was tested. Results We demonstrate that affinities as low as 10−7 M are sufficient to activate mast cells in vitro and drive allergic reactions in vivo. Low‐affinity IgE antibodies are able to do so, since they bind allergens bivalently on the surface of mast cells, leading to high‐avidity interactions. Conclusions These results suggest that the underlying mechanism of allergen cross‐reactivity may be low‐affinity but high‐avidity binding between IgE antibodies and cross‐reactive allergen.
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Affiliation(s)
- Xinyue Chang
- International Immunology Center Anhui Agricultural University Anhui China
- Immunology RIA, Inselspital University of Bern Bern Switzerland
| | - Lisha Zha
- International Immunology Center Anhui Agricultural University Anhui China
- Immunology RIA, Inselspital University of Bern Bern Switzerland
| | | | - Mona O. Mohsen
- International Immunology Center Anhui Agricultural University Anhui China
| | - Pascal Krenger
- International Immunology Center Anhui Agricultural University Anhui China
| | - Xuelan Liu
- International Immunology Center Anhui Agricultural University Anhui China
- Immunology RIA, Inselspital University of Bern Bern Switzerland
| | - Monique Vogel
- International Immunology Center Anhui Agricultural University Anhui China
| | - Martin F. Bachmann
- International Immunology Center Anhui Agricultural University Anhui China
- Immunology RIA, Inselspital University of Bern Bern Switzerland
- Nuffield Department of Medicine Centre for Cellular and Molecular Physiology (CCMP) The Jenner Institute, University of Oxford Oxford UK
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Intracellular delivery of trehalose renders mesenchymal stromal cells viable and immunomodulatory competent after cryopreservation. Cytotechnology 2021; 73:391-411. [PMID: 33875905 PMCID: PMC8047578 DOI: 10.1007/s10616-021-00465-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 03/19/2021] [Indexed: 12/04/2022] Open
Abstract
Trehalose is a nontoxic disaccharide and a promising cryoprotection agent for medically applicable cells. In this study, the efficiency of combining trehalose with reversible electroporation for cryopreservation of two types of human mesenchymal stromal cells was investigated: adipose-derived stromal cells, and umbilical-cord-derived stromal cells. Comparable results to standard dimethyl sulfoxide cryopreservation protocols were achieved, even without extensive electroporation parameters and protocol optimization. The presence of high extracellular trehalose resulted in comparable cell viabilities without and with electroporation. According to the determination of trehalose concentrations, 250 mM extracellular trehalose resulting in, 20 mM to 50 mM intracellular trehalose were sufficient for successful cryopreservation of cells. With electroporation, higher (i.e. 50 mM to 90 mM) intracellular trehalose was achieved after cryopreservation, although cell survival was not improved significantly. To evaluate the impact of electroporation and cryopreservation on cells, stress and immune-activation-related gene expression were analyzed. Electroporation and/or cryopreservation resulted in increased SOD2 and HSPA1A expression. Despite the increased stress response, the high up-regulation by mesenchymal stromal cells of immunomodulatory genes in the inflammatory environment was not affected. Highest expression was seen for the IDO1 and TSG6 genes. In conclusion, cryopreservation of mesenchymal stromal cells in trehalose results in comparable characteristics to their cryopreservation using dimethyl sulfoxide.
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Yan Z, Yin L, Hao C, Liu K, Qiu J. Synergistic effect of pulsed electric fields and temperature on the inactivation of microorganisms. AMB Express 2021; 11:47. [PMID: 33759040 PMCID: PMC7988035 DOI: 10.1186/s13568-021-01206-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 03/15/2021] [Indexed: 12/28/2022] Open
Abstract
Pulsed electric fields (PEF) as a new pasteurization technology played an important role in the process of inactivating microorganisms. At the same time, temperature could promote the process of electroporation, and achieve better inactivation effect. This article studied the inactivation effect of PEF on Saccharomyces cerevisiae, Escherichia coli, and Bacillus velezensis under different initial temperatures (room temperature-24 \documentclass[12pt]{minimal}
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\begin{document}$$\mathrm{^\circ{\rm C} }$$\end{document}∘C). From the inactivation results, it found temperature could reduce the critical electric field intensity for microbial inactivation. After the irreversible electroporation of microorganisms occurred, the nucleic acid content and protein content in the suspension increased with the inactivation rate because the cell membrane integrity was destroyed. We had proved that the electric field and temperature could promote molecular transport through the finite element simulation. Under the same initial temperature and electrical parameters (electric field intensity, pulse width, pulse number), the lethal effect on different microorganisms was Saccharomyces cerevisiae > Escherichia coli > Bacillus velezensis.
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Potočnik T, Miklavčič D, Maček Lebar A. Gene transfer by electroporation with high frequency bipolar pulses in vitro. Bioelectrochemistry 2021; 140:107803. [PMID: 33975183 DOI: 10.1016/j.bioelechem.2021.107803] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 03/16/2021] [Accepted: 03/17/2021] [Indexed: 12/21/2022]
Abstract
High-frequency bipolar pulses (HF-BP) have been demonstrated to be efficient for membrane permeabilization and irreversible electroporation. Since membrane permeabilization has been achieved using HF-BP pulses we hypothesized that with these pulses we can also achieve successful gene electrotransfer (GET). Three variations of bursts of 2 µs bipolar pulses with 2 µs interphase delay were applied in HF-BP protocols. We compared transfection efficiency of monopolar micro and millisecond pulses and HF-BP protocols at various plasmid DNA (pDNA) concentrations on CHO - K1 cells. GET efficiency increased with increasing pDNA concentration. Overall GET obtained by HF-BP pulse protocols was comparable to overall GET obtained by longer monopolar pulse protocols. Our results, however, suggest that although we were able to achieve similar percent of transfected cells, the number of pDNA copies that were successfully transferred into cells seemed to be higher when longer monopolar pulses were used. Interestingly, we did not observe any direct correlation between fluorescence intensity of pDNA aggregates formed on cell membrane and transfection efficiency. The results of our study confirmed that we can achieve successful GET with bipolar microsecond i. e. HF-BP pulses, although at the expense of higher pDNA concentrations.
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Affiliation(s)
- Tjaša Potočnik
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška 25, 1000 Ljubljana, Slovenia
| | - Damijan Miklavčič
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška 25, 1000 Ljubljana, Slovenia
| | - Alenka Maček Lebar
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška 25, 1000 Ljubljana, Slovenia.
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Abstract
Accurate estimation of in vivo clearance in human is pivotal to determine the dose and dosing regimen for drug development. In vitro-in vivo extrapolation (IVIVE) has been performed to predict drug clearance using empirical and physiological scalars. Multiple in vitro systems and mathematical modeling techniques have been employed to estimate in vivo clearance. The models for predicting clearance have significantly improved and have evolved to become more complex by integrating multiple processes such as drug metabolism and transport as well as passive diffusion. This chapter covers the use of conventional as well as recently developed methods to predict metabolic and transporter-mediated clearance along with the advantages and disadvantages of using these methods and the associated experimental considerations. The general approaches to improve IVIVE by use of appropriate scalars, incorporation of extrahepatic metabolism and transport and application of physiologically based pharmacokinetic (PBPK) models with proteomics data are also discussed. The chapter also provides an overview of the advantages of using such dynamic mechanistic models over static models for clearance predictions to improve IVIVE.
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18
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Ganeva V, Angelova B, Galutzov B, Goltsev V, Zhiponova M. Extraction of Proteins and Other Intracellular Bioactive Compounds From Baker's Yeasts by Pulsed Electric Field Treatment. Front Bioeng Biotechnol 2020; 8:552335. [PMID: 33384987 PMCID: PMC7770146 DOI: 10.3389/fbioe.2020.552335] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 11/23/2020] [Indexed: 11/13/2022] Open
Abstract
Yeasts are rich source of proteins, antioxidants, vitamins, and other bioactive compounds. The main drawback in their utilization as valuable ingredients in functional foods and dietary supplements production is the thick, indigestible cell wall, as well as the high nucleic acid content. In this study, we evaluated the feasibility of pulsed electric field (PEF) treatment as an alternative method for extraction of proteins and other bioactive intracellular compounds from yeasts. Baker's yeast water suspensions with different concentration (12.5-85 g dry cell weight per liter) were treated with monopolar rectangular pulses using a continuous flow system. The PEF energy required to achieve irreversible electropermeabilization was significantly reduced with the increase of the biomass concentration. Upon incubation of the permeabilized cells in water, only relatively small intracellular compounds were released. Release of 90% of the free amino acids and low molecular UV absorbing compounds, 80% of the glutathione, and ∼40% of the total phenol content was achieved about 2 h after pulsation and incubation of the suspensions at room temperature. At these conditions, the macromolecules (proteins and nucleic acids) were retained largely inside. Efficient protein release (∼90% from the total soluble protein) occurred only after dilution and incubation of the permeabilized cells in buffer with pH 8-9. Protein concentrates obtained by ultrafiltration (10 kDa cut off) had lower nucleic acid content (protein/nucleic acid ratio ∼100/4.5) in comparison with cell lysates obtained by mechanical disintegration. The obtained results allowed to conclude that PEF treatment can be used as an efficient alternative approach for production of yeast extracts with different composition, suitable for application in food, cosmetics and pharmaceutical industries.
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Affiliation(s)
- Valentina Ganeva
- Biological Faculty, Sofia University “St. Kl. Ohridski”, Sofia, Bulgaria
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19
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Fesmire CC, Petrella RA, Kaufman JD, Topasna N, Sano MB. Irreversible electroporation is a thermally mediated ablation modality for pulses on the order of one microsecond. Bioelectrochemistry 2020; 135:107544. [DOI: 10.1016/j.bioelechem.2020.107544] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 04/29/2020] [Accepted: 04/29/2020] [Indexed: 12/15/2022]
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20
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Vaessen EMJ, Kemme HA, Timmermans RAH, Schutyser MAI, den Besten HMW. Temperature and presence of ethanol affect accumulation of intracellular trehalose in Lactobacillus plantarum WCFS1 upon pulsed electric field treatment. Bioelectrochemistry 2020; 137:107680. [PMID: 33120293 DOI: 10.1016/j.bioelechem.2020.107680] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 09/19/2020] [Accepted: 09/24/2020] [Indexed: 11/17/2022]
Abstract
Pulsed electric field (PEF) treatment can be used to increase intracellular small molecule concentrations in bacteria, which can lead to enhanced robustness of these cells during further processing. In this study we investigated the effects of the PEF treatment temperature and the presence of 8% (v/v) ethanol in the PEF medium on cell survival, membrane fluidity and intracellular trehalose concentrations of Lactobacillus plantarum WCFS1. A moderate PEF treatment temperature of 21 °C resulted in a high cell survival combined with higher intracellular trehalose concentrations compared to a treatment at 10 and 35 °C. Interestingly, highest intracellular trehalose concentrations were observed upon supplementing the PEF medium with 8% ethanol, which resulted in more than a doubling in intracellular trehalose concentrations, while culture survival was retained. Overall, this study shows that treatment temperature and PEF medium optimization are important directions for improving molecule uptake upon PEF processing.
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Affiliation(s)
- E M J Vaessen
- Food Process Engineering, Wageningen University and Research, P.O. Box 17, 6700 AA Wageningen, the Netherlands; Food Microbiology, Wageningen University and Research, P.O. Box 17, 6700 AA Wageningen, the Netherlands
| | - H A Kemme
- Food Process Engineering, Wageningen University and Research, P.O. Box 17, 6700 AA Wageningen, the Netherlands; Food Microbiology, Wageningen University and Research, P.O. Box 17, 6700 AA Wageningen, the Netherlands
| | - R A H Timmermans
- Wageningen Food and Biobased Research, Wageningen University and Research, P.O. Box 17, 6700 AA Wageningen, the Netherlands
| | - M A I Schutyser
- Food Process Engineering, Wageningen University and Research, P.O. Box 17, 6700 AA Wageningen, the Netherlands
| | - H M W den Besten
- Food Microbiology, Wageningen University and Research, P.O. Box 17, 6700 AA Wageningen, the Netherlands.
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21
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Petrella RA, Fesmire CC, Kaufman JD, Topasna N, Sano MB. Algorithmically Controlled Electroporation: A Technique for Closed Loop Temperature Regulated Pulsed Electric Field Cancer Ablation. IEEE Trans Biomed Eng 2020; 67:2176-2186. [PMID: 32673194 DOI: 10.1109/tbme.2019.2956537] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To evaluate the effect of a closed-loop temperature based feedback algorithm on ablative outcomes for pulsed electric field treatments. METHODS A 3D tumor model of glioblastoma was used to assess the impact of 2 μs duration bipolar waveforms on viability following exposure to open and closed-loop protocols. Closed-loop treatments evaluated transient temperature increases of 5, 10, 15, or 22 °C above baseline. RESULTS The temperature controlled ablation diameters were conditionally different than the open-loop treatments and closed-loop treatments generally produced smaller ablations. Closed-loop control enabled the investigation of treatments with steady state 42 °C hyperthermic conditions which were not feasible without active feedback. Baseline closed-loop treatments at 20 °C resulted in ablations measuring 9.9 ± 0.3 mm in diameter while 37 °C treatments were 20% larger (p < 0.0001) measuring 11.8 ± 0.3 mm indicating that this protocol induces a thermally mediated biological response. CONCLUSION A closed-loop control algorithm which modulated the delay between successive pulse waveforms to achieve stable target temperatures was demonstrated. Algorithmic control enabled the evaluation of specific treatment parameters at physiological temperatures not possible with open-loop systems due to excessive Joule heating. SIGNIFICANCE Irreversible electroporation is generally considered to be a non-thermal ablation modality and temperature monitoring is not part of the standard clinical practice. The results of this study indicate ablative outcomes due to exposure to pulses on the order of one microsecond may be thermally mediated and dependent on local tissue temperatures. The results of this study set the foundation for experiments in vivo utilizing temperature control algorithms.
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22
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Polajžer T, Dermol-Černe J, Reberšek M, O'Connor R, Miklavčič D. Cancellation effect is present in high-frequency reversible and irreversible electroporation. Bioelectrochemistry 2019; 132:107442. [PMID: 31923714 DOI: 10.1016/j.bioelechem.2019.107442] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 12/03/2019] [Accepted: 12/05/2019] [Indexed: 12/21/2022]
Abstract
It was recently suggested that applying high-frequency short biphasic pulses (HF-IRE) reduces pain and muscle contractions in electrochemotherapy and irreversible ablation treatments; however, higher amplitudes with HF-IRE pulses are required to achieve a similar effect as with monophasic pulses. HF-IRE pulses are in the range of a microseconds, thus, the so-called cancellation effect could be responsible for the need to apply pulses of higher amplitudes. In cancellation effect, the effect of first pulse is reduced by the second pulse of opposite polarity. We evaluated cancellation effect with high-frequency biphasic pulses on CHO-K1 in different electroporation buffers. We applied eight bursts of 1-10 µs long pulses with inter-phase delays of 0.5 µs - 10 ms and evaluated membrane permeability and cell survival. In permeability experiments, cancellation effect was not observed in low-conductivity buffer. Cancellation effect was, however, observed in treatments with high-frequency biphasic pulses looking at survival in all of the tested electroporation buffers. In general, cancellation effect depended on inter-phase delay as well as on pulse duration, i.e. longer pulses and longer interphase delay cause less pronounced cancellation effect. Cancellation effect could be partially explained by the assisted discharge and not by the hyperpolarization by the chloride channels.
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Affiliation(s)
- Tamara Polajžer
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška 25, 1000 Ljubljana, Slovenia
| | - Janja Dermol-Černe
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška 25, 1000 Ljubljana, Slovenia
| | - Matej Reberšek
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška 25, 1000 Ljubljana, Slovenia
| | - Rodney O'Connor
- École des Mines de Saint-Étienne, Department of Bioelectronics, Georges Charpak Campus, Centre Microélectronique de Provence, 880 Route de Mimet, 13120 Gardanne, France
| | - Damijan Miklavčič
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška 25, 1000 Ljubljana, Slovenia.
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Kim HB, Lee S, Shen Y, Ryu PD, Lee Y, Chung JH, Sung CK, Baik KY. Physicochemical factors that affect electroporation of lung cancer and normal cell lines. Biochem Biophys Res Commun 2019; 517:703-708. [PMID: 31387747 DOI: 10.1016/j.bbrc.2019.07.119] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 07/30/2019] [Indexed: 01/04/2023]
Abstract
Electroporation is used for cancer therapy to efficiently destroy cancer tissues by transferring anticancer drugs into cancer cells or by irreversible tumor ablation without resealing pores. There is growing interest in the electroporation method for the treatment of lung cancer, which has the highest mortality rate among cancers. Improving the cancer cell selectivity has the potential to expand its use. However, the factors that influence the cell selectivity of electroporation are debatable. We aimed to identify the important factors that influence the efficiency of electroporation in lung cells. The electropermeabilization of lung cancer cells (H460, A549, and HCC1588) and normal lung cells (MRC5, WI26 and L132) was evaluated by the transfer of fluorescence dyes. We found that membrane permeabilization increased as cell size, membrane stiffness, resting transmembrane potential, and lipid cholesterol ratio increased. Among them, lipid composition was found to be the most relevant factor in the electroporation of lung cells. Our results provide insight into the differences between lung cancer cells and normal lung cells and provide a basis for enhancing the sensitivity of lung cancers cells to electroporation.
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Affiliation(s)
- Hong Bae Kim
- Department of Biosystems & Biomaterials Science and Engineering, Seoul National University, Seoul, 08826, South Korea
| | - Seho Lee
- Department of Brain and Cognitive Engineering, Korea University, Seoul, 02841, South Korea
| | - Yiming Shen
- Department of Veterinary Pharmacology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, 08826, South Korea
| | - Pan-Dong Ryu
- Department of Veterinary Pharmacology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, 08826, South Korea
| | - Yunmi Lee
- Department of Chemistry, Kwangwoon University, Seoul, 01897, South Korea
| | - Jong Hoon Chung
- Department of Biosystems & Biomaterials Science and Engineering, Seoul National University, Seoul, 08826, South Korea
| | - Chang Kyu Sung
- Department of Radiology, Seoul National University College of Medicine, Seoul, 07061, South Korea.
| | - Ku Youn Baik
- Department of Electrical and Biological Physics, Kwangwoon University, Seoul, 01897, South Korea.
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Hoejholt KL, Mužić T, Jensen SD, Dalgaard LT, Bilgin M, Nylandsted J, Heimburg T, Frandsen SK, Gehl J. Calcium electroporation and electrochemotherapy for cancer treatment: Importance of cell membrane composition investigated by lipidomics, calorimetry and in vitro efficacy. Sci Rep 2019; 9:4758. [PMID: 30894594 PMCID: PMC6427041 DOI: 10.1038/s41598-019-41188-z] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 02/20/2019] [Indexed: 12/21/2022] Open
Abstract
Calcium electroporation is a novel anti-cancer treatment investigated in clinical trials. We explored cell sensitivity to calcium electroporation and electroporation with bleomycin, using viability assays at different time and temperature points, as well as heat calorimetry, lipidomics, and flow cytometry. Three cell lines: HT29 (colon cancer), MDA-MB231 (breast cancer), and HDF-n (normal fibroblasts) were investigated for; (a) cell survival dependent on time of addition of drug relative to electroporation (1.2 kV/cm, 8 pulses, 99 µs, 1 Hz), at different temperatures (37 °C, 27 °C, 17 °C); (b) heat capacity profiles obtained by differential scanning calorimetry without added calcium; (c) lipid composition by mass spectrometry; (d) phosphatidylserine in the plasma membrane outer leaflet using flow cytometry. Temperature as well as time of drug administration affected treatment efficacy in HT29 and HDF-n cells, but not MDA-MB231 cells. Interestingly the HT29 cell line displayed a higher phase transition temperature (approximately 20 °C) versus 14 °C (HDF-n) and 15 °C (MDA-MB231). Furthermore the HT29 cell membranes had a higher ratio of ethers to esters, and a higher expression of phosphatidylserine in the outer leaflet. In conclusion, lipid composition and heat capacity of the membrane might influence permeabilisation of cells and thereby the effect of calcium electroporation and electrochemotherapy.
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Affiliation(s)
- K L Hoejholt
- Center for Experimental Drug and Gene Electrotransfer, Department of Oncology, Copenhagen University Hospital Herlev, Herlev, Denmark
| | - T Mužić
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - S D Jensen
- Center for Experimental Drug and Gene Electrotransfer, Department of Oncology, Copenhagen University Hospital Herlev, Herlev, Denmark
| | - L T Dalgaard
- Department of Science and Environment, Roskilde University, Roskilde, Denmark
| | - M Bilgin
- Danish Cancer Society Research Center (DCRC), Copenhagen, Denmark
| | - J Nylandsted
- Danish Cancer Society Research Center (DCRC), Copenhagen, Denmark
| | - T Heimburg
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - S K Frandsen
- Center for Experimental Drug and Gene Electrotransfer, Department of Oncology, Copenhagen University Hospital Herlev, Herlev, Denmark.
- Center for Experimental Drug and Gene Electrotransfer, Department of Clinical Oncology and Palliative Care, Zealand University Hospital, Roskilde, Denmark.
| | - J Gehl
- Center for Experimental Drug and Gene Electrotransfer, Department of Oncology, Copenhagen University Hospital Herlev, Herlev, Denmark.
- Center for Experimental Drug and Gene Electrotransfer, Department of Clinical Oncology and Palliative Care, Zealand University Hospital, Roskilde, Denmark.
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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Kotnik T, Rems L, Tarek M, Miklavčič D. Membrane Electroporation and Electropermeabilization: Mechanisms and Models. Annu Rev Biophys 2019; 48:63-91. [PMID: 30786231 DOI: 10.1146/annurev-biophys-052118-115451] [Citation(s) in RCA: 322] [Impact Index Per Article: 64.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Exposure of biological cells to high-voltage, short-duration electric pulses causes a transient increase in their plasma membrane permeability, allowing transmembrane transport of otherwise impermeant molecules. In recent years, large steps were made in the understanding of underlying events. Formation of aqueous pores in the lipid bilayer is now a widely recognized mechanism, but evidence is growing that changes to individual membrane lipids and proteins also contribute, substantiating the need for terminological distinction between electroporation and electropermeabilization. We first revisit experimental evidence for electrically induced membrane permeability, its correlation with transmembrane voltage, and continuum models of electropermeabilization that disregard the molecular-level structure and events. We then present insights from molecular-level modeling, particularly atomistic simulations that enhance understanding of pore formation, and evidence of chemical modifications of membrane lipids and functional modulation of membrane proteins affecting membrane permeability. Finally, we discuss the remaining challenges to our full understanding of electroporation and electropermeabilization.
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Affiliation(s)
- Tadej Kotnik
- Faculty of Electrical Engineering, University of Ljubljana, SI-1000 Ljubljana, Slovenia; ,
| | - Lea Rems
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, 17165 Solna, Sweden;
| | - Mounir Tarek
- Université de Lorraine, CNRS, LPCT, F-54000 Nancy, France;
| | - Damijan Miklavčič
- Faculty of Electrical Engineering, University of Ljubljana, SI-1000 Ljubljana, Slovenia; ,
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Kanduser M, Kokalj Imsirovic M, Usaj M. The Effect of Lipid Antioxidant α-Tocopherol on Cell Viability and Electrofusion Yield of B16-F1 Cells In Vitro. J Membr Biol 2019; 252:105-114. [DOI: 10.1007/s00232-019-00059-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 01/16/2019] [Indexed: 10/27/2022]
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Edelblute CM, Guo S, Hornef J, Yang E, Jiang C, Schoenbach K, Heller R. Moderate Heat Application Enhances the Efficacy of Nanosecond Pulse Stimulation for the Treatment of Squamous Cell Carcinoma. Technol Cancer Res Treat 2019; 17:1533033818802305. [PMID: 30253713 PMCID: PMC6156209 DOI: 10.1177/1533033818802305] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Nanosecond pulse stimulation as a tumor ablation therapy has been studied for the treatment of various carcinomas in animal models and has shown a significant survival benefit. In the current study, we found that moderate heating at 43°C for 2 minutes significantly enhanced in vitro nanosecond pulse stimulation-induced cell death of KLN205 murine squamous cell carcinoma cells by 2.43-fold at 600 V and by 2.32-fold at 900 V, as evidenced by propidium iodide uptake. Furthermore, the ablation zone in KLN205 cells placed in a 3-dimensional cell-culture model and pulsed at a voltage of 900 V at 43°C was 3 times larger than in cells exposed to nanosecond pulse stimulation at room temperature. Application of moderate heating alone did not cause cell death. A nanosecond pulse stimulation electrode with integrated controllable laser heating was developed to treat murine ectopic squamous cell carcinoma. With this innovative system, we were able to quickly heat and maintain the temperature of the target tumor at 43°C during nanosecond pulse stimulation. Nanosecond pulse stimulation with moderate heating was shown to significantly extend overall survival, delay tumor growth, and achieve a high rate of complete tumor regression. Moderate heating extended survival nearly 3-fold where median overall survival was 22 days for 9.8 kV without moderate heating and over 63 days for tumors pulsed with 600, 100 ns pulses at 5 Hz, at voltage of 9.8 kV with moderate heating. Median overall survival in the control groups was 24 and 31 days for mice with untreated tumors and tumors receiving moderate heat alone, respectively. Nearly 69% (11 of 16) of tumor-bearing mice treated with nanosecond pulse stimulation with moderate heating were tumor free at the completion of the study, whereas complete tumor regression was not observed in the control groups and in 9.8 kV without moderate heating. These results suggest moderate heating can reduce the necessary applied voltage for tumor ablation with nanosecond pulse stimulation.
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Affiliation(s)
- Chelsea M Edelblute
- 1 Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA, USA
| | - Siqi Guo
- 1 Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA, USA
| | - James Hornef
- 1 Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA, USA.,2 Department of Biomedical Engineering, College of Engineering, Old Dominion University, Norfolk, VA, USA
| | - Enbo Yang
- 1 Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA, USA
| | - Chunqi Jiang
- 1 Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA, USA.,2 Department of Biomedical Engineering, College of Engineering, Old Dominion University, Norfolk, VA, USA
| | - Karl Schoenbach
- 1 Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA, USA.,3 School of Medical Diagnostic & Translational Sciences, College of Health Sciences, Old Dominion University, Norfolk, VA, USA
| | - Richard Heller
- 1 Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA, USA.,3 School of Medical Diagnostic & Translational Sciences, College of Health Sciences, Old Dominion University, Norfolk, VA, USA
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Stewart MP, Langer R, Jensen KF. Intracellular Delivery by Membrane Disruption: Mechanisms, Strategies, and Concepts. Chem Rev 2018; 118:7409-7531. [PMID: 30052023 PMCID: PMC6763210 DOI: 10.1021/acs.chemrev.7b00678] [Citation(s) in RCA: 382] [Impact Index Per Article: 63.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Intracellular delivery is a key step in biological research and has enabled decades of biomedical discoveries. It is also becoming increasingly important in industrial and medical applications ranging from biomanufacture to cell-based therapies. Here, we review techniques for membrane disruption-based intracellular delivery from 1911 until the present. These methods achieve rapid, direct, and universal delivery of almost any cargo molecule or material that can be dispersed in solution. We start by covering the motivations for intracellular delivery and the challenges associated with the different cargo types-small molecules, proteins/peptides, nucleic acids, synthetic nanomaterials, and large cargo. The review then presents a broad comparison of delivery strategies followed by an analysis of membrane disruption mechanisms and the biology of the cell response. We cover mechanical, electrical, thermal, optical, and chemical strategies of membrane disruption with a particular emphasis on their applications and challenges to implementation. Throughout, we highlight specific mechanisms of membrane disruption and suggest areas in need of further experimentation. We hope the concepts discussed in our review inspire scientists and engineers with further ideas to improve intracellular delivery.
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Affiliation(s)
- Martin P. Stewart
- Department of Chemical Engineering, Massachusetts Institute
of Technology, Cambridge, USA
- The Koch Institute for Integrative Cancer Research,
Massachusetts Institute of Technology, Cambridge, USA
| | - Robert Langer
- Department of Chemical Engineering, Massachusetts Institute
of Technology, Cambridge, USA
- The Koch Institute for Integrative Cancer Research,
Massachusetts Institute of Technology, Cambridge, USA
| | - Klavs F. Jensen
- Department of Chemical Engineering, Massachusetts Institute
of Technology, Cambridge, USA
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Calcein Release from Cells In Vitro via Reversible and Irreversible Electroporation. J Membr Biol 2017; 251:119-130. [DOI: 10.1007/s00232-017-0005-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Accepted: 11/09/2017] [Indexed: 01/19/2023]
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30
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Effect of pulsed electrical fields on the structural properties that affect french fry texture during processing. Trends Food Sci Technol 2017. [DOI: 10.1016/j.tifs.2017.05.016] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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31
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Li X, Dunevall J, Ren L, Ewing AG. Mechanistic Aspects of Vesicle Opening during Analysis with Vesicle Impact Electrochemical Cytometry. Anal Chem 2017; 89:9416-9423. [PMID: 28776974 DOI: 10.1021/acs.analchem.7b02226] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Vesicle impact electrochemical cytometry (VIEC) has been used to quantify the vesicular transmitter content in mammalian vesicles. In the present study, we studied the mechanism of VIEC by quantifying the catecholamine content in single vesicles isolated from pheochromocytoma (PC12) cells. These vesicles contain about one tenth of the catecholamine compared with adrenal chromaffin vesicles. The existence of a prespike foot for many events suggests the formation of an initial transiently stable pore at the beginning of vesicle rupture. Increasing the detection temperature from 6 to 30 °C increases the possibility of vesicle rupture on the electrode, implying that there is a temperature-dependent process that facilitates electroporation. Natively larger vesicles are shown to rupture earlier and more frequently than smaller ones in VIEC. Likewise, manipulating vesicle content and size with drugs leads to similar trends. These data support the hypothesis that electroporation is the primary force for pore opening in VIEC. We further hypothesize that a critical step for initiating vesicle opening by electroporation is diffusion of membrane proteins away from the membrane region of contact with the electrode to allow closer contact, increasing the lateral potential field and thus facilitating electroporation.
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Affiliation(s)
- Xianchan Li
- Department of Chemistry and Molecular Biology, University of Gothenburg , Kemivägen 10, 41296 Gothenburg, Sweden
| | - Johan Dunevall
- Department of Chemical and Chemical Engineering, Chalmers University of Technology , Kemivägen 10, 41296 Gothenburg, Sweden
| | - Lin Ren
- Department of Chemical and Chemical Engineering, Chalmers University of Technology , Kemivägen 10, 41296 Gothenburg, Sweden
| | - Andrew G Ewing
- Department of Chemistry and Molecular Biology, University of Gothenburg , Kemivägen 10, 41296 Gothenburg, Sweden.,Department of Chemical and Chemical Engineering, Chalmers University of Technology , Kemivägen 10, 41296 Gothenburg, Sweden
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Kandušer M, Belič A, Čorović S, Škrjanc I. Modular Serial Flow Through device for pulsed electric field treatment of the liquid samples. Sci Rep 2017; 7:8115. [PMID: 28808315 PMCID: PMC5556104 DOI: 10.1038/s41598-017-08620-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 07/11/2017] [Indexed: 11/25/2022] Open
Abstract
In biotechnology, medicine, and food processing, simple and reliable methods for cell membrane permeabilization are required for drug/gene delivery into the cells or for the inactivation of undesired microorganisms. Pulsed electric field treatment is among the most promising methods enabling both aims. The drawback in current technology is controllable large volume operation. To address this challenge, we have developed an experimental setup for flow through electroporation with online regulation of the flow rate with feedback control. We have designed a modular serial flow-through co-linear chamber with a smooth inner surface, the uniform cross-section geometry through the majority of the system’s length, and the mesh in contact with the electrodes, which provides uniform electric field distribution and fluid velocity equilibration. The cylindrical cross-section of the chamber prevents arching at the active treatment region. We used mathematical modeling for the evaluation of electric field distribution and the flow profile in the active region. The system was tested for the inactivation of Escherichia coli. We compared two flow-through chambers and used a static chamber as a reference. The experiments were performed under identical experimental condition (product and similar process parameters). The data were analyzed in terms of inactivation efficiency and specific energy consumption.
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Affiliation(s)
- Maša Kandušer
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška 25, SI-1000, Ljubljana, Slovenia
| | - Aleš Belič
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška 25, SI-1000, Ljubljana, Slovenia
| | - Selma Čorović
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška 25, SI-1000, Ljubljana, Slovenia
| | - Igor Škrjanc
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška 25, SI-1000, Ljubljana, Slovenia.
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Endocytic uptake of monomeric amyloid-β peptides is clathrin- and dynamin-independent and results in selective accumulation of Aβ(1-42) compared to Aβ(1-40). Sci Rep 2017; 7:2021. [PMID: 28515429 PMCID: PMC5435687 DOI: 10.1038/s41598-017-02227-9] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 04/10/2017] [Indexed: 01/05/2023] Open
Abstract
Intraneuronal accumulation of amyloid-β (Aβ) peptides represent an early pathological feature in Alzheimer’s disease. We have therefore utilized flow cytometry and confocal microscopy in combination with endocytosis inhibition to explore the internalisation efficiency and uptake mechanisms of Aβ(1–40) and Aβ(1–42) monomers in cultured SH-SY5Y cells. We find that both variants are constitutively internalised via endocytosis and that their uptake is proportional to cellular endocytic rate. Moreover, SH-SY5Y cells internalise consistently twice the amount of Aβ(1–42) compared to Aβ(1–40); an imaging-based quantification showed that cells treated with 1 µM peptide for 8 h contained 800,000 peptides of Aβ(1–42) and 400,000 of Aβ(1–40). Both variants co-localised to >90% with lysosomes or other acidic compartments. Dynasore and chlorpromazine endocytosis inhibitors were both found to reduce uptake, particularly of Aβ(1–42). Overexpression of the C-terminal of the clathrin-binding domain of AP180, dynamin2 K44A, or Arf6 Q67L did however not reduce uptake of the Aβ variants. By contrast, perturbation of actin polymerisation and inhibition of macropinocytosis reduced Aβ(1–40) and Aβ(1–42) uptake considerably. This study clarifies mechanisms of Aβ(1–40) and Aβ(1–42) uptake, pinpoints differences between the two variants and highlights a common and putative role of macropinocytosis in the early accumulation of intraneuronal Aβ in AD.
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Yoshikado T, Toshimoto K, Nakada T, Ikejiri K, Kusuhara H, Maeda K, Sugiyama Y. Comparison of Methods for Estimating Unbound Intracellular-to-Medium Concentration Ratios in Rat and Human Hepatocytes Using Statins. Drug Metab Dispos 2017; 45:779-789. [DOI: 10.1124/dmd.116.074823] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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35
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Effect of cell membrane fatty acid composition of Escherichia coli on the resistance to pulsed electric field (PEF) treatment. Lebensm Wiss Technol 2017. [DOI: 10.1016/j.lwt.2016.10.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Ou QX, Nikolic-Jaric M, Gänzle M. Mechanisms of inactivation of Candida humilis and Saccharomyces cerevisiae by pulsed electric fields. Bioelectrochemistry 2016; 115:47-55. [PMID: 28063751 DOI: 10.1016/j.bioelechem.2016.12.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 12/28/2016] [Accepted: 12/28/2016] [Indexed: 10/20/2022]
Abstract
AIMS This study aimed to determine how electric field strength, pulse width and shape, and specific energy input relate to the effect of pulsed electric fields (PEF) on viability and membrane permeabilization in Candida humilis and Saccharomyces cerevisiae suspended in potassium phosphate buffer. METHODS AND RESULTS Cells were treated with a micro-scale system with parallel plate electrodes. Propidium iodide was added before or after treatments to differentiate between reversible and irreversible membrane permeabilization. Treatments of C. humilis with 71kV/cm and 48kJ/kg reduced cell counts by 3.9±0.6 log (cfu/mL). Pulse shape or width had only a small influence on the treatment lethality. Variation of electric field strength (17-71kV/cm), pulse width (0.086-4μs), and specific energy input (8-46kJ/kg) demonstrated that specific energy input correlated to the membrane permeabilization (r2=0.84), while other parameters were uncorrelated. A minimum energy input of 3 and 12kJ/kg was required to achieve reversible membrane permeabilization and a reduction of cell counts, respectively, of C. humilis. CONCLUSIONS Energy input was the parameter that best described the inactivation efficiency of PEF. SIGNIFICANCE AND IMPACT OF STUDY This study is an important step to identify key process parameters and to facilitate process design for improved cost-effectiveness of commercial PEF treatment.
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Affiliation(s)
- Qi-Xing Ou
- University of Alberta, Dept. of Agricultural, Food and Nutritional Science, Edmonton, Canada
| | | | - Michael Gänzle
- University of Alberta, Dept. of Agricultural, Food and Nutritional Science, Edmonton, Canada; Hubei University of Technology, School of Food and Pharmaceutical Engineering, Wuhan, China.
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Cebrián G, Condón S, Mañas P. Influence of growth and treatment temperature on Staphylococcus aureus resistance to pulsed electric fields: Relationship with membrane fluidity. INNOV FOOD SCI EMERG 2016. [DOI: 10.1016/j.ifset.2016.08.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Haberl-Meglič S, Levičnik E, Luengo E, Raso J, Miklavčič D. The effect of temperature and bacterial growth phase on protein extraction by means of electroporation. Bioelectrochemistry 2016; 112:77-82. [PMID: 27561651 DOI: 10.1016/j.bioelechem.2016.08.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Revised: 08/01/2016] [Accepted: 08/15/2016] [Indexed: 11/27/2022]
Abstract
Different chemical and physical methods are used for extraction of proteins from bacteria, which are used in variety of fields. But on a large scale, many methods have severe drawbacks. Recently, extraction by means of electroporation showed a great potential to quickly obtain proteins from bacteria. Since many parameters are affecting the yield of extracted proteins, our aim was to investigate the effect of temperature and bacterial growth phase on the yield of extracted proteins. At the same time bacterial viability was tested. Our results showed that the temperature has a great effect on protein extraction, the best temperature post treatment being 4°C. No effect on bacterial viability was observed for all temperatures tested. Also bacterial growth phase did not affect the yield of extracted proteins or bacterial viability. Nevertheless, further experiments may need to be performed to confirm this observation, since only one incubation temperature (4°C) and one incubation time before and after electroporation (0.5 and 1h) were tested for bacterial growth phase. Based on our results we conclude that temperature is a key element for bacterial membrane to stay in a permeabilized state, so more proteins flow out of bacteria into surrounding media.
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Affiliation(s)
- Saša Haberl-Meglič
- University of Ljubljana, Faculty of Electrical Engineering, Trzaska 25, 1000 Ljubljana, Slovenia
| | - Eva Levičnik
- University of Ljubljana, Faculty of Electrical Engineering, Trzaska 25, 1000 Ljubljana, Slovenia
| | - Elisa Luengo
- University of Zaragoza, Faculty of Veterinary, Zaragoza, Spain
| | - Javier Raso
- University of Zaragoza, Faculty of Veterinary, Zaragoza, Spain
| | - Damijan Miklavčič
- University of Ljubljana, Faculty of Electrical Engineering, Trzaska 25, 1000 Ljubljana, Slovenia.
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Kulkarni P, Korzekwa K, Nagar S. Intracellular Unbound Atorvastatin Concentrations in the Presence of Metabolism and Transport. J Pharmacol Exp Ther 2016; 359:26-36. [PMID: 27451408 DOI: 10.1124/jpet.116.235689] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 07/20/2016] [Indexed: 12/26/2022] Open
Abstract
Accurate prediction of drug target activity and rational dosing regimen design require knowledge of drug concentrations at the target. It is important to understand the impact of processes such as membrane permeability, partitioning, and active transport on intracellular drug concentrations. The present study aimed to predict intracellular unbound atorvastatin concentrations and characterize the effect of enzyme-transporter interplay on these concentrations. Single-pass liver perfusion studies were conducted in rats using atorvastatin (ATV, 1 µM) alone at 4°C and at 37°C in presence of rifampin (RIF, 20 µM) and 1-aminobenzotriazole (ABT, 1 mM), separately and in combination. The unbound intracellular ATV concentration was predicted with a five-compartment explicit membrane model using the parameterized diffusional influx clearance, active basolateral uptake clearance, and metabolic clearance. Chemical inhibition of uptake and metabolism at 37°C proved to be better controls relative to studies at 4°C. The predicted unbound intracellular concentration at the end of the 50-minute perfusion in the +ABT , +ABT+RIF, and the ATV-only groups was 6.5 µM, 0.58 µM, and 5.14 µM, respectively. The predicted total liver concentrations and amount recovered in bile were within 0.94-1.3 fold of the observed value in all groups. The fold difference in total liver concentration did not always extrapolate to the fold difference in predicted unbound concentration across groups. Together, these results support the use of compartmental modeling to predict intracellular concentrations in dynamic organ-based systems. These predictions can provide insight into the role of uptake transporters and metabolizing enzymes in determining drug tissue concentrations.
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Affiliation(s)
- Priyanka Kulkarni
- Department of Pharmaceutical Sciences, Temple University School of Pharmacy, Philadelphia, Pennsylvania
| | - Kenneth Korzekwa
- Department of Pharmaceutical Sciences, Temple University School of Pharmacy, Philadelphia, Pennsylvania
| | - Swati Nagar
- Department of Pharmaceutical Sciences, Temple University School of Pharmacy, Philadelphia, Pennsylvania
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40
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Liu ZW, Han Z, Zeng XA, Sun DW, Aadil RM. Effects of vesicle components on the electro-permeability of lipid bilayers of vesicles induced by pulsed electric fields (PEF) treatment. J FOOD ENG 2016. [DOI: 10.1016/j.jfoodeng.2016.02.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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41
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Bodénès P, Lopes F, Pareau D, Français O, Le Pioufle B. Microdevice for studying the in situ permeabilization and characterization of Chlamydomonas reinhardtii in lipid accumulation phase. ALGAL RES 2016. [DOI: 10.1016/j.algal.2016.03.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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42
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Room temperature electrocompetent bacterial cells improve DNA transformation and recombineering efficiency. Sci Rep 2016; 6:24648. [PMID: 27095488 PMCID: PMC4837392 DOI: 10.1038/srep24648] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 04/04/2016] [Indexed: 01/20/2023] Open
Abstract
Bacterial competent cells are essential for cloning, construction of DNA libraries, and mutagenesis in every molecular biology laboratory. Among various transformation methods, electroporation is found to own the best transformation efficiency. Previous electroporation methods are based on washing and electroporating the bacterial cells in ice-cold condition that make them fragile and prone to death. Here we present simple temperature shift based methods that improve DNA transformation and recombineering efficiency in E. coli and several other gram-negative bacteria thereby economizing time and cost. Increased transformation efficiency of large DNA molecules is a significant advantage that might facilitate the cloning of large fragments from genomic DNA preparations and metagenomics samples.
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Mishra A, Maltais TR, Walter TM, Wei A, Williams SJ, Wereley ST. Trapping and viability of swimming bacteria in an optoelectric trap. LAB ON A CHIP 2016; 16:1039-1046. [PMID: 26891971 PMCID: PMC5562368 DOI: 10.1039/c5lc01559f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Non-contact manipulation methods capable of trapping and transporting swimming bacteria can significantly aid in chemotaxis studies. However, high swimming speed makes the trapping of these organisms an inherently challenging task. We demonstrate that an optoelectric technique, rapid electrokinetic patterning (REP), can effectively trap and manipulate Enterobacter aerogenes bacteria swimming at velocities greater than 20 μm s(-1). REP uses electro-orientation, laser-induced AC electrothermal flow, and particle-electrode interactions for capturing these cells. In contrast to trapping non-swimming bacteria and inert microspheres, we observe that electro-orientation is critical to the trapping of the swimming cells, since unaligned bacteria can swim faster than the radially inward electrothermal flow and escape the trap. By assessing the cell membrane integrity, we study the effect of REP trapping conditions, including optical radiation, laser-induced heating, and the electric field on cell viability. When applied individually, the optical radiation and laser-induced heating have negligible effect on cells. At the standard REP trapping conditions fewer than 2% of cells have a compromised membrane after four minutes. To our knowledge this is the first study detailing the effect of REP trapping on cell viability. The presented results provide a clear guideline on selecting suitable REP parameters for trapping living bacteria.
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Affiliation(s)
- A Mishra
- Department of Mechanical Engineering and Birck Nanotechnology Center, Purdue University, West Lafayette, 47907, USA.
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Guionet A, David F, Zaepffel C, Coustets M, Helmi K, Cheype C, Packan D, Garnier JP, Blanckaert V, Teissié J. E. coli electroeradication on a closed loop circuit by using milli-, micro- and nanosecond pulsed electric fields: Comparison between energy costs. Bioelectrochemistry 2015; 103:65-73. [DOI: 10.1016/j.bioelechem.2014.08.021] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 07/25/2014] [Accepted: 08/12/2014] [Indexed: 01/30/2023]
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45
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Liu ZW, Zeng XA, Sun DW, Han Z, Aadil RM. Synergistic effect of thermal and pulsed electric field (PEF) treatment on the permeability of soya PC and DPPC vesicles. J FOOD ENG 2015. [DOI: 10.1016/j.jfoodeng.2014.12.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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46
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Jain A, Shah SG, Chugh A. Cell Penetrating Peptides as Efficient Nanocarriers for Delivery of Antifungal Compound, Natamycin for the Treatment of Fungal Keratitis. Pharm Res 2014; 32:1920-30. [DOI: 10.1007/s11095-014-1586-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 11/24/2014] [Indexed: 12/01/2022]
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Abstract
Environmental temperature can have a surprising impact on extremity growth in homeotherms, but the underlying mechanisms have remained elusive for over a century. Limbs of animals raised at warm ambient temperature are significantly and permanently longer than those of littermates housed at cooler temperature. These remarkably consistent lab results closely resemble the ecogeographical tenet described by Allen's "extremity size rule," that appendage length correlates with temperature and latitude. This phenotypic growth plasticity could have adaptive significance for thermal physiology. Shortened extremities help retain body heat in cold environments by decreasing surface area for potential heat loss. Homeotherms have evolved complex mechanisms to maintain tightly regulated internal temperatures in challenging environments, including "facultative extremity heterothermy" in which limb temperatures can parallel ambient. Environmental modulation of tissue temperature can have direct and immediate consequences on cell proliferation, metabolism, matrix production, and mineralization in cartilage. Temperature can also indirectly influence cartilage growth by modulating circulating levels and delivery routes of essential hormones and paracrine regulators. Using an integrated approach, this article synthesizes classic studies with new data that shed light on the basis and significance of this enigmatic growth phenomenon and its relevance for treating human bone elongation disorders. Discussion centers on the vasculature as a gateway to understanding the complex interconnection between direct (local) and indirect (systemic) mechanisms of temperature-enhanced bone lengthening. Recent advances in imaging modalities that enable the dynamic study of cartilage growth plates in vivo will be key to elucidating fundamental physiological mechanisms of long bone growth regulation.
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Affiliation(s)
- Maria A Serrat
- Department of Anatomy and Pathology, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia
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Cholet C, Delsart C, Petrel M, Gontier E, Grimi N, L'hyvernay A, Ghidossi R, Vorobiev E, Mietton-Peuchot M, Gény L. Structural and biochemical changes induced by pulsed electric field treatments on Cabernet Sauvignon grape berry skins: impact on cell wall total tannins and polysaccharides. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2014; 62:2925-34. [PMID: 24617601 DOI: 10.1021/jf404804d] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Pulsed electric field (PEF) treatment is an emerging technology that is arousing increasing interest in vinification processes for its ability to enhance polyphenol extraction performance. The aim of this study was to investigate the effects of PEF treatment on grape skin histocytological structures and on the organization of skin cell wall polysaccharides and tannins, which, until now, have been little investigated. This study relates to the effects of two PEF treatments on harvested Cabernet Sauvignon berries: PEF1 (medium strength (4 kV/cm); short duration (1 ms)) and PEF2 (low intensity (0.7 kV/cm); longer duration (200 ms)). Histocytological observations and the study of levels of polysaccharidic fractions and total amounts of tannins allowed differentiation between the two treatments. Whereas PEF1 had little effect on the polyphenol structure and pectic fraction, PEF2 profoundly modified the organization of skin cell walls. Depending on the PEF parameters, cell wall structure was differently affected, providing variable performance in terms of polyphenol extraction and wine quality.
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Affiliation(s)
- Céline Cholet
- Université de Bordeaux, Institut des Sciences de la Vigne et du Vin , EA 4577, Unité de recherche œnologie, France
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Serrat MA, Efaw ML, Williams RM. Hindlimb heating increases vascular access of large molecules to murine tibial growth plates measured by in vivo multiphoton imaging. J Appl Physiol (1985) 2014; 116:425-38. [PMID: 24371019 PMCID: PMC3921350 DOI: 10.1152/japplphysiol.01212.2013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 12/23/2013] [Indexed: 01/30/2023] Open
Abstract
Advances in understanding the molecular regulation of longitudinal growth have led to development of novel drug therapies for growth plate disorders. Despite progress, a major unmet challenge is delivering therapeutic agents to avascular-cartilage plates. Dense extracellular matrix and lack of penetrating blood vessels create a semipermeable "barrier," which hinders molecular transport at the vascular-cartilage interface. To overcome this obstacle, we used a hindlimb heating model to manipulate bone circulation in 5-wk-old female mice (n = 22). Temperatures represented a physiological range of normal human knee joints. We used in vivo multiphoton microscopy to quantify temperature-enhanced delivery of large molecules into tibial growth plates. We tested the hypothesis that increasing hindlimb temperature from 22°C to 34°C increases vascular access of large systemic molecules, modeled using 10, 40, and 70 kDa dextrans that approximate sizes of physiological regulators. Vascular access was quantified by vessel diameter, velocity, and dextran leakage from subperichondrial plexus vessels and accumulation in growth plate cartilage. Growth plate entry of 10 kDa dextrans increased >150% at 34°C. Entry of 40 and 70 kDa dextrans increased <50%, suggesting a size-dependent temperature enhancement. Total dextran levels in the plexus increased at 34°C, but relative leakage out of vessels was not temperature dependent. Blood velocity and vessel diameter increased 118% and 31%, respectively, at 34°C. These results demonstrate that heat enhances vascular carrying capacity and bioavailability of large molecules around growth plates, suggesting that temperature could be a noninvasive strategy for modulating delivery of therapeutics to impaired growth plates of children.
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Affiliation(s)
- Maria A Serrat
- Department of Anatomy and Pathology, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia
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Vázquez M, Vélez D, Devesa V. In vitro characterization of the intestinal absorption of methylmercury using a Caco-2 cell model. Chem Res Toxicol 2014; 27:254-64. [PMID: 24397474 DOI: 10.1021/tx4003758] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Methylmercury (CH3Hg) is one of the forms of mercury found in food, particularly in seafood. Exposure to CH3Hg is associated with neurotoxic effects during development. In addition, methylmercury has been classified by the International Agency for Research on Cancer as a possible human carcinogen. Although the diet is known to be the main source of exposure, few studies have characterized the mechanisms involved in the absorption of this contaminant. The present study examines the absorption process using the Caco-2 cell line as a model of the intestinal epithelium. The results indicate that transport across the intestinal cell monolayer in an absorptive direction occurs mainly through passive transcellular diffusion. This mechanism coexists with carrier-mediated transcellular transport, which has an active component. The participation of H(+)- and Na(+)-dependent transport was observed. Inhibition tests point to the possible participation of amino acid transporters (B(0,+) system, L system, and/or y(+)L system) and organic anion transporters (OATs). Our study suggests the participation in CH3Hg absorption of transporters that have already been identified as being responsible for the transport of this species in other systems, although further studies are needed to confirm their participation in intestinal absorption. It should be noted that CH3Hg experiences important cellular acumulation (48-78%). Considering the toxic nature of this contaminant, this fact could affect intestinal epithelium function.
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Affiliation(s)
- Marta Vázquez
- Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC) , Avenida Agustín Escardino 7, 46980 Paterna, Valencia, Spain
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