The Experts below are selected from a list of 201 Experts worldwide ranked by ideXlab platform
Eiji Tokunaga - One of the best experts on this subject based on the ideXlab platform.
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Noninvasive and Safe Cell Viability Assay for Breast Cancer MCF-7 Cells Using Natural Food Pigment.
Biology, 2020Co-Authors: Kyohei Yamashita, Ryoma Tagawa, Yoshikazu Higami, Eiji TokunagaAbstract:A dye exclusion test (DET) was performed to determine the viability of human breast cancer cells MCF-7, using natural Food Pigments as compared with trypan blue (TB), a typical synthetic dye for DET known to exhibit teratogenicity and cytotoxicity. We demonstrated that Monascus Pigment (MP) is noninvasive to living cells and can effectively stain only dead cells. This study is the first verification of the applicability of MP to cancer cells. The appropriate MP concentration was 0.4% (0.02% as the concentration of pure MP) and all the dead cells were stained within 10 min. We found that the cell proliferation or the reduced nicotinamide adenine dinucleotide (NADH) activity of living cells was maintained over 48 h. Although 0.1% TB did not show an increase in dead cells, a marked decrease in NADH activity was confirmed. In addition, even when MP coexisted with cisplatin, staining of dead cells was maintained for 47 h, indicating stability to drugs (reagents). The cost of MP is estimated to be about 1/10 of TB. The fact that MP can be used as a cell viability determination reagent for Euglena and Paramecium, as shown in preceding papers, and also for MCF-7, as shown in this paper, indicates the possibility of application in more cells of different species.
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Noninvasive and safe cell viability assay for Euglena gracilis using natural Food Pigment
PeerJ, 2019Co-Authors: Kyohei Yamashita, Koji Yamada, Kengo Suzuki, Eiji TokunagaAbstract:Noninvasive and safe cell viability assay is required in many fields such as regenerative medicine, genetic engineering, single-cell analysis, and microbial Food culture. In this case, a safe and inexpensive method which is a small load on cells and the environment is preferable without requiring expensive and space-consuming equipment and a technician to operate. We examined eight typical natural Food Pigments to find Monascus Pigment (MP) or anthocyanin Pigment (AP) works as a good viability indicator of dye exclusion test (DET) for Euglena gracilis which is an edible photosynthetic green microalga. This is the first report using natural Food Pigments as cell viability assay. Euglena gracilis stained by MP or AP can be visually judged with a bright field microscope. This was spectrally confirmed by scan-free, non-invasive absorbance spectral imaging A(x, y, λ) microscopy of single live cells and principal component analysis (PCA). To confirm the ability of staining dead cells and examine the load on the cells, these two natural Pigments were compared with trypan blue (TB) and methylene blue (MP), which are synthetic dyes conventionally used for DET. As a result, MP and AP had as good ability of staining dead cells treated with microwave as TB and MB and showed faster and more uniform staining for dead cells in benzalkonium chloride than them. The growth curve and the ratio of dead cells in the culture showed that the synthetic dyes inhibit the growth of E. gracilis, but the natural Pigments do not. As the cell density increased, however, AP increased the ratio of stained cells, which was prevented by the addition of glucose. MP can stain dead cells in a shorter time than AP, while AP is more stable in color against long-term irradiation of intense light than MP. Due to the low toxicity of these Pigments, viability of cells in culture can be monitored with them over a long period.
Kyohei Yamashita - One of the best experts on this subject based on the ideXlab platform.
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Noninvasive and Safe Cell Viability Assay for Breast Cancer MCF-7 Cells Using Natural Food Pigment.
Biology, 2020Co-Authors: Kyohei Yamashita, Ryoma Tagawa, Yoshikazu Higami, Eiji TokunagaAbstract:A dye exclusion test (DET) was performed to determine the viability of human breast cancer cells MCF-7, using natural Food Pigments as compared with trypan blue (TB), a typical synthetic dye for DET known to exhibit teratogenicity and cytotoxicity. We demonstrated that Monascus Pigment (MP) is noninvasive to living cells and can effectively stain only dead cells. This study is the first verification of the applicability of MP to cancer cells. The appropriate MP concentration was 0.4% (0.02% as the concentration of pure MP) and all the dead cells were stained within 10 min. We found that the cell proliferation or the reduced nicotinamide adenine dinucleotide (NADH) activity of living cells was maintained over 48 h. Although 0.1% TB did not show an increase in dead cells, a marked decrease in NADH activity was confirmed. In addition, even when MP coexisted with cisplatin, staining of dead cells was maintained for 47 h, indicating stability to drugs (reagents). The cost of MP is estimated to be about 1/10 of TB. The fact that MP can be used as a cell viability determination reagent for Euglena and Paramecium, as shown in preceding papers, and also for MCF-7, as shown in this paper, indicates the possibility of application in more cells of different species.
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Noninvasive and safe cell viability assay for Euglena gracilis using natural Food Pigment
PeerJ, 2019Co-Authors: Kyohei Yamashita, Koji Yamada, Kengo Suzuki, Eiji TokunagaAbstract:Noninvasive and safe cell viability assay is required in many fields such as regenerative medicine, genetic engineering, single-cell analysis, and microbial Food culture. In this case, a safe and inexpensive method which is a small load on cells and the environment is preferable without requiring expensive and space-consuming equipment and a technician to operate. We examined eight typical natural Food Pigments to find Monascus Pigment (MP) or anthocyanin Pigment (AP) works as a good viability indicator of dye exclusion test (DET) for Euglena gracilis which is an edible photosynthetic green microalga. This is the first report using natural Food Pigments as cell viability assay. Euglena gracilis stained by MP or AP can be visually judged with a bright field microscope. This was spectrally confirmed by scan-free, non-invasive absorbance spectral imaging A(x, y, λ) microscopy of single live cells and principal component analysis (PCA). To confirm the ability of staining dead cells and examine the load on the cells, these two natural Pigments were compared with trypan blue (TB) and methylene blue (MP), which are synthetic dyes conventionally used for DET. As a result, MP and AP had as good ability of staining dead cells treated with microwave as TB and MB and showed faster and more uniform staining for dead cells in benzalkonium chloride than them. The growth curve and the ratio of dead cells in the culture showed that the synthetic dyes inhibit the growth of E. gracilis, but the natural Pigments do not. As the cell density increased, however, AP increased the ratio of stained cells, which was prevented by the addition of glucose. MP can stain dead cells in a shorter time than AP, while AP is more stable in color against long-term irradiation of intense light than MP. Due to the low toxicity of these Pigments, viability of cells in culture can be monitored with them over a long period.
Linn Voss - One of the best experts on this subject based on the ideXlab platform.
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Intestinal and hepatic effects of iron oxide nanoparticles
Archives of Toxicology, 2021Co-Authors: Linn Voss, Valerie Stock, Albert Braeuning, Linda Böhmert, Elisa Hoché, Andreas F. Thünemann, Holger SiegAbstract:Iron oxide nanoparticles gain increasing attention due to their broad industrial use. However, safety concerns exist since their effects on human cells are still under investigation. The presence of iron oxide nanoparticles in the Food Pigment E172 has been shown recently. Here, we studied four iron oxide nanoparticles, one Food Pigment E172 and the ionic control FeSO_4 regarding dissolution in biological media, uptake and transport, and cellular effects in vitro in human intestinal Caco-2 and HepaRG hepatocarcinoma cells. The iron oxide nanoparticles passed the gastrointestinal passage without dissolution and reached the intestine in the form of particles. Minor uptake was seen into Caco-2 cells but almost no transport to the basolateral site was detected for any of the tested particles. HepaRG cells showed higher particle uptake. Caco-2 cells showed no alterations in reactive oxygen species production, apoptosis, or mitochondrial membrane potential, whereas two particles induced apoptosis in HepaRG cells, and one altered mitochondrial membrane potential at non-cytotoxic concentrations. No correlation between physicochemical particle characteristics and cellular effects was observed, thus emphasizing the need for case-by-case assessment of iron oxide nanoparticles.
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Impact of iron oxide nanoparticles on xenobiotic metabolism in HepaRG cells
Archives of Toxicology, 2020Co-Authors: Linn Voss, Kiymet Yilmaz, Lea Burkard, Janja Vidmar, Valerie Stock, Ute Hoffmann, Oliver Pötz, Helen Sophie Hammer, Matthias Peiser, Albert BraeuningAbstract:Iron oxide nanoparticles are used in various industrial fields, as a tool in biomedicine as well as in Food colorants, and can therefore reach human metabolism via oral uptake or injection. However, their effects on the human body, especially the liver as one of the first target organs is still under elucidation. Here, we studied the influence of different representative iron oxide materials on xenobiotic metabolism of HepaRG cells. These included four iron oxide nanoparticles, one commercially available yellow Food Pigment (E172), and non-particulate ionic control FeSO_4. The nanoparticles had different chemical and crystalline structures and differed in size and shape and were used at a concentration of 50 µg Fe/mL. We found that various CYP enzymes were downregulated by some but not all iron oxide nanoparticles, with the Fe_3O_4-particle, both γ -Fe_2O_3-particles, and FeSO_4 exhibiting the strongest effects, the yellow Food Pigment E172 showing a minor effect and an α -Fe_2O_3 nanoparticle leading to almost no inhibition of phase I machinery. The downregulation was seen at the mRNA, protein expression, and activity levels. Thereby, no dependency on the size or chemical structure was found. This underlines the difficulty of the grouping of nanomaterials regarding their physiological impact, suggesting that every iron oxide nanoparticle species needs to be evaluated in a case-by-case approach.
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The presence of iron oxide nanoparticles in the Food Pigment E172.
Food chemistry, 2020Co-Authors: Linn Voss, Janja Vidmar, Valerie Stock, Albert Braeuning, I-lun Hsiao, Maximilian Ebisch, Nadine Dreiack, Linda Böhmert, Katrin Loeschner, Peter LauxAbstract:Abstract Iron oxides used as Food colorants are listed in the European Union with the number E172. However, there are no specifications concerning the fraction of nanoparticles in these Pigments. Here, seven E172 products were thoroughly characterized. Samples of all colors were analyzed with a broad spectrum of methods to assess their physico-chemical properties. Small-Angle X-ray Scattering (SAXS), Dynamic Light Scattering (DLS), Transmission Electron Microscopy (TEM), zeta-potential, Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), X-ray diffraction (XRD), Brunauer-Emmett-Teller analysis (BET), Asymmetric Flow Field-Flow Fractionation (AF4) and in vitro cell viability measurements were used. Nanoparticles were detected in all E172 samples by TEM or SAXS measurements. Quantitative results from both methods were comparable. Five Pigments were evaluated by TEM, of which four had a size median below 100 nm, while SAXS showed a size median below 100 nm for six evaluated Pigments. Therefore, consumers may be exposed to iron oxide nanoparticles through the consumption of Food Pigments.
Albert Braeuning - One of the best experts on this subject based on the ideXlab platform.
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Intestinal and hepatic effects of iron oxide nanoparticles
Archives of Toxicology, 2021Co-Authors: Linn Voss, Valerie Stock, Albert Braeuning, Linda Böhmert, Elisa Hoché, Andreas F. Thünemann, Holger SiegAbstract:Iron oxide nanoparticles gain increasing attention due to their broad industrial use. However, safety concerns exist since their effects on human cells are still under investigation. The presence of iron oxide nanoparticles in the Food Pigment E172 has been shown recently. Here, we studied four iron oxide nanoparticles, one Food Pigment E172 and the ionic control FeSO_4 regarding dissolution in biological media, uptake and transport, and cellular effects in vitro in human intestinal Caco-2 and HepaRG hepatocarcinoma cells. The iron oxide nanoparticles passed the gastrointestinal passage without dissolution and reached the intestine in the form of particles. Minor uptake was seen into Caco-2 cells but almost no transport to the basolateral site was detected for any of the tested particles. HepaRG cells showed higher particle uptake. Caco-2 cells showed no alterations in reactive oxygen species production, apoptosis, or mitochondrial membrane potential, whereas two particles induced apoptosis in HepaRG cells, and one altered mitochondrial membrane potential at non-cytotoxic concentrations. No correlation between physicochemical particle characteristics and cellular effects was observed, thus emphasizing the need for case-by-case assessment of iron oxide nanoparticles.
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Impact of iron oxide nanoparticles on xenobiotic metabolism in HepaRG cells
Archives of Toxicology, 2020Co-Authors: Linn Voss, Kiymet Yilmaz, Lea Burkard, Janja Vidmar, Valerie Stock, Ute Hoffmann, Oliver Pötz, Helen Sophie Hammer, Matthias Peiser, Albert BraeuningAbstract:Iron oxide nanoparticles are used in various industrial fields, as a tool in biomedicine as well as in Food colorants, and can therefore reach human metabolism via oral uptake or injection. However, their effects on the human body, especially the liver as one of the first target organs is still under elucidation. Here, we studied the influence of different representative iron oxide materials on xenobiotic metabolism of HepaRG cells. These included four iron oxide nanoparticles, one commercially available yellow Food Pigment (E172), and non-particulate ionic control FeSO_4. The nanoparticles had different chemical and crystalline structures and differed in size and shape and were used at a concentration of 50 µg Fe/mL. We found that various CYP enzymes were downregulated by some but not all iron oxide nanoparticles, with the Fe_3O_4-particle, both γ -Fe_2O_3-particles, and FeSO_4 exhibiting the strongest effects, the yellow Food Pigment E172 showing a minor effect and an α -Fe_2O_3 nanoparticle leading to almost no inhibition of phase I machinery. The downregulation was seen at the mRNA, protein expression, and activity levels. Thereby, no dependency on the size or chemical structure was found. This underlines the difficulty of the grouping of nanomaterials regarding their physiological impact, suggesting that every iron oxide nanoparticle species needs to be evaluated in a case-by-case approach.
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The presence of iron oxide nanoparticles in the Food Pigment E172.
Food chemistry, 2020Co-Authors: Linn Voss, Janja Vidmar, Valerie Stock, Albert Braeuning, I-lun Hsiao, Maximilian Ebisch, Nadine Dreiack, Linda Böhmert, Katrin Loeschner, Peter LauxAbstract:Abstract Iron oxides used as Food colorants are listed in the European Union with the number E172. However, there are no specifications concerning the fraction of nanoparticles in these Pigments. Here, seven E172 products were thoroughly characterized. Samples of all colors were analyzed with a broad spectrum of methods to assess their physico-chemical properties. Small-Angle X-ray Scattering (SAXS), Dynamic Light Scattering (DLS), Transmission Electron Microscopy (TEM), zeta-potential, Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), X-ray diffraction (XRD), Brunauer-Emmett-Teller analysis (BET), Asymmetric Flow Field-Flow Fractionation (AF4) and in vitro cell viability measurements were used. Nanoparticles were detected in all E172 samples by TEM or SAXS measurements. Quantitative results from both methods were comparable. Five Pigments were evaluated by TEM, of which four had a size median below 100 nm, while SAXS showed a size median below 100 nm for six evaluated Pigments. Therefore, consumers may be exposed to iron oxide nanoparticles through the consumption of Food Pigments.
Valerie Stock - One of the best experts on this subject based on the ideXlab platform.
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Intestinal and hepatic effects of iron oxide nanoparticles
Archives of Toxicology, 2021Co-Authors: Linn Voss, Valerie Stock, Albert Braeuning, Linda Böhmert, Elisa Hoché, Andreas F. Thünemann, Holger SiegAbstract:Iron oxide nanoparticles gain increasing attention due to their broad industrial use. However, safety concerns exist since their effects on human cells are still under investigation. The presence of iron oxide nanoparticles in the Food Pigment E172 has been shown recently. Here, we studied four iron oxide nanoparticles, one Food Pigment E172 and the ionic control FeSO_4 regarding dissolution in biological media, uptake and transport, and cellular effects in vitro in human intestinal Caco-2 and HepaRG hepatocarcinoma cells. The iron oxide nanoparticles passed the gastrointestinal passage without dissolution and reached the intestine in the form of particles. Minor uptake was seen into Caco-2 cells but almost no transport to the basolateral site was detected for any of the tested particles. HepaRG cells showed higher particle uptake. Caco-2 cells showed no alterations in reactive oxygen species production, apoptosis, or mitochondrial membrane potential, whereas two particles induced apoptosis in HepaRG cells, and one altered mitochondrial membrane potential at non-cytotoxic concentrations. No correlation between physicochemical particle characteristics and cellular effects was observed, thus emphasizing the need for case-by-case assessment of iron oxide nanoparticles.
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Impact of iron oxide nanoparticles on xenobiotic metabolism in HepaRG cells
Archives of Toxicology, 2020Co-Authors: Linn Voss, Kiymet Yilmaz, Lea Burkard, Janja Vidmar, Valerie Stock, Ute Hoffmann, Oliver Pötz, Helen Sophie Hammer, Matthias Peiser, Albert BraeuningAbstract:Iron oxide nanoparticles are used in various industrial fields, as a tool in biomedicine as well as in Food colorants, and can therefore reach human metabolism via oral uptake or injection. However, their effects on the human body, especially the liver as one of the first target organs is still under elucidation. Here, we studied the influence of different representative iron oxide materials on xenobiotic metabolism of HepaRG cells. These included four iron oxide nanoparticles, one commercially available yellow Food Pigment (E172), and non-particulate ionic control FeSO_4. The nanoparticles had different chemical and crystalline structures and differed in size and shape and were used at a concentration of 50 µg Fe/mL. We found that various CYP enzymes were downregulated by some but not all iron oxide nanoparticles, with the Fe_3O_4-particle, both γ -Fe_2O_3-particles, and FeSO_4 exhibiting the strongest effects, the yellow Food Pigment E172 showing a minor effect and an α -Fe_2O_3 nanoparticle leading to almost no inhibition of phase I machinery. The downregulation was seen at the mRNA, protein expression, and activity levels. Thereby, no dependency on the size or chemical structure was found. This underlines the difficulty of the grouping of nanomaterials regarding their physiological impact, suggesting that every iron oxide nanoparticle species needs to be evaluated in a case-by-case approach.
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The presence of iron oxide nanoparticles in the Food Pigment E172.
Food chemistry, 2020Co-Authors: Linn Voss, Janja Vidmar, Valerie Stock, Albert Braeuning, I-lun Hsiao, Maximilian Ebisch, Nadine Dreiack, Linda Böhmert, Katrin Loeschner, Peter LauxAbstract:Abstract Iron oxides used as Food colorants are listed in the European Union with the number E172. However, there are no specifications concerning the fraction of nanoparticles in these Pigments. Here, seven E172 products were thoroughly characterized. Samples of all colors were analyzed with a broad spectrum of methods to assess their physico-chemical properties. Small-Angle X-ray Scattering (SAXS), Dynamic Light Scattering (DLS), Transmission Electron Microscopy (TEM), zeta-potential, Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), X-ray diffraction (XRD), Brunauer-Emmett-Teller analysis (BET), Asymmetric Flow Field-Flow Fractionation (AF4) and in vitro cell viability measurements were used. Nanoparticles were detected in all E172 samples by TEM or SAXS measurements. Quantitative results from both methods were comparable. Five Pigments were evaluated by TEM, of which four had a size median below 100 nm, while SAXS showed a size median below 100 nm for six evaluated Pigments. Therefore, consumers may be exposed to iron oxide nanoparticles through the consumption of Food Pigments.