49 results on '"Sramkova M"'
Search Results
2. Konference o katalogizaci evropských lidových balad v Norsku
- Author
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Šrámková, M.
- Published
- 1971
3. Parabens and Their Relation to Obesity.
- Author
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KOLATOROVA, L., SRAMKOVA, M., VITKU, J., VCELAK, J., LISCHKOVA, O., STARKA, L., and DUSKOVA, M.
- Subjects
PARABENS ,OBESITY ,ESTROGEN ,MENSTRUAL cycle ,RESISTIN - Abstract
Parabens are a group of chemicals used as preservatives in the food, cosmetic and pharmaceutical industries. They are known to possess estrogenic effects, and therefore have been classified as endocrine disruptors. In addition to the classical endocrine organs, other tissues have endocrine activity, including adipose tissue. Several chemicals are known to cause obesogenic effects, and parabens are currently being studied in this context. The aim of this study was to investigate the possible connections of paraben exposure and obesity. Blood plasma from 27 healthy women was collected during their menstrual cycle. Basal anthropometric measures, levels of parabens (methylparaben, ethylparaben and propylparaben), adipokines (adiponectin, adipsin, leptin, resistin and visfatin) and hormones affecting energy balance and metabolic health (c-peptide, ghreline, GIP, GLP-1, glucagon, insulin, PAI-1) were measured. A Kolmogorov- Smirnov test showed higher methylparaben and propylparaben levels in women with BMI 25-34.9 compared to those with BMI 18.5-24.9. Plasma levels of methylparaben as well as the sum of parabens were positively associated with the plasma adipsin levels. Negative associations for methylparaben were found for glucagon, leptin and PAI-1. In accordance with other experimental studies we observed important associations of methylparaben and hormones affecting energy balance and metabolic health, indicating its obesogenic potential. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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4. Can the Gold Standard Be Beaten? How Reliable Are Various Modifications of the Synacthen Test Compared to the Insulin Tolerance Test.
- Author
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KOSAK, M., DUSKOVA, M., STARKA, L., JANDIKOVA, H., POSPISILOVA, H., SRAMKOVA, M., HANA, V., KRSEK, M., SPRINGER, D., and SIMUNKOVA, K.
- Subjects
ROUTINE diagnostic tests ,HYDROCORTISONE ,ADRENAL insufficiency ,ADRENAL diseases ,ADRENAL glands - Abstract
Criteria for the evaluation of the insulin tolerance test (ITT) and Synacthen test are still a matter of debate. The objective of the study was to make a comparison of serum and salivary cortisol during four stimulation tests. Sixty four healthy volunteers underwent the ITT, the Synacthen test with 1 (LDST), 10 (MDST) and 250 (HDST) μg dose of ACTH. Maximum serum cortisol response was observed at the 90 min of the ITT (49 %), HDST (89 %) and MDST (56 %) and at the 40 min of the LDST (44 %). Results expressed as 95 % confidence intervals: 408.0-843.6 and 289.5-868.1 nmol/l in the IIT at 60 and 90 min. In the HDST and the MDST serum cortisol reached the maximum at 90 min 542.6-1245.5 and 444.2-871.3 nmol/l. Levels of salivary cortisol followed the same pattern as serum cortisol. Salivary cortisol reached the maximum response in the HDST and the MDST at 90 min and at 40 min in the LDST. We confirmed good reliability of all tests with respect to timing of response and maximum response compared to the ITT. We proved that the MDST test can provide the similar response in serum cortisol to the HDST. Measuring either salivary cortisol or ACTH levels did not provide any additional benefit then measuring serum cortisol by itself. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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5. Response of Cortisol Metabolites in the Insulin Tolerance Test and Synacthen Tests.
- Author
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SIMUNKOVA, K., DUSKOVA, M., KOSAK, M., KRSEK, M., HANA, V., HILL, M., JANDIKOVA, H., POSPISILOVA, H., SRAMKOVA, M., BIFULCO, E., and STARKA, L.
- Subjects
HYDROCORTISONE ,METABOLITES ,INSULIN resistance ,COMPARATIVE studies ,ADRENAL diseases - Abstract
Determination of response of cortisol and its metabolites to different stimuli may be important for adrenal gland disorders. To date, only one metabolite, cortisone, has been followed in stimulation tests of the adrenal gland. We aimed to describe a response of cortisol metabolites to the standard short Synacthen test (HDST), insulin tolerance test (ITT), low dose Synacthen test (LDST) and medium dose Synacthen test (MDST). Sixty healthy subjects were investigated: 30 men and 30 women. Plasma for measurements of cortisol and its metabolites was obtained before and 30th and 60th min after Synacthen and insulin administration. The cut-off 500 nmol/l of cortisol was reached after stimulation in all of tests, the maximal stimulation level was reached in 60th min in all of the tests except for LDST. The response of cortisol and its metabolites at 30th and 60th min strongly correlated in all of the tests except for LDST. Cortisol and its metabolites increased after stimulation; in contrast, cortisone and its metabolites decreased. We showed that the response of the cortisol metabolites during the Synacthen tests and ITT well correlated, and the MDST showed similar response compared to HDST. The decrease in cortisone metabolites may correspond to the regeneration of cortisol from cortisone in response to stimulation test. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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6. Consumer Behaviour of Generation Z in the Context of Dual Quality of Daily Consumption Products on EU market
- Author
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Šramková Marianna and Sirotiaková Mária
- Subjects
dual quality ,z generation ,non-food products ,consumer behaviour ,Social Sciences - Abstract
Research background: The paper focuses on the issue of dual quality of daily consumption products through the lens of the Z generation. Z generation is a generation of people born between years of 1997-2012, a generation that will become the main purchasing power in a few years. Purpose of the article: The purpose of the research was to explore the possibility whether the information on dual product quality affects the consumer behaviour of members of Z generation and if so, to what extent and at what type of products. Methods: Main method to receive necessary data for analyse was a questionnaire and its statistical evaluation given hypothesis. The research was carried out in the form of a survey consisted of 227 consumers. Findings & Value added: The results show that 85% of them had dual quality information, perceived this issue as a serious problem, and the majority wants to be informed more about this issue. More than half of the Z generation had changed their consumer behaviour as a result of information about the dual quality of goods on market of European Union, especially women with higher education and the Z generation living in rural areas. Research confirmed that the change in behaviour mainly concerns non-food products such as cosmetics and clothing.
- Published
- 2021
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7. Safety evaluation of an extension of use of the food enzyme α-amylase from the non-genetically modified Bacillus amyloliquefaciens strain AE-BAA.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Cavanna D, di Piazza G, and Liu Y
- Abstract
The food enzyme α-amylase (4-α-d-glucan glucanohydrolase; EC 3.2.1.1) is produced with the non-genetically modified microorganism Bacillus amyloliquefaciens strain AE-BAA by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in eight food manufacturing processes. Subsequently, the applicant has requested to extend its use to include one additional process and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of nine food manufacturing processes. As the food enzyme-total organic solids (TOS) are removed from the final foods in two food manufacturing processes, the dietary exposure to the food enzyme-TOS was estimated only for the remaining seven processes. Dietary exposure was calculated to be up to 5.833 mg TOS/kg body weight per day in European populations. Based on the previous evaluation, the assessment of the new data and the revised dietary exposure, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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8. Safety evaluation of the food enzyme glucan-1,4-α-glucosidase from the non-genetically modified Aspergillus niger strain DP-Azh100.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Aguilera J, Andryszkiewicz M, Cavanna D, Marini E, Peluso S, Cabo LS, Ferreira de Sousa R, and Liu Y
- Abstract
The food enzyme glucan-1,4-α-glucosidase (4-α-d-glucan glucohydrolase; EC 3.2.1.3) is produced with the non-genetically modified Aspergillus niger strain DP-Azh100 by Genencor International B.V. It was considered free from viable cells of the production organism. The food enzyme is intended to be used in four food manufacturing processes. Since residual amounts of total organic solids (TOS) are removed in two processes, dietary exposure was calculated only for the two remaining processes. It was estimated to be up to 1.390 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level at the highest dose tested of 1000 mg TOS/kg bw per day, which when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 719. A search for the homology of the amino acid sequence of the food enzyme to known allergens was made and one match to a respiratory allergen was found. Known sources of food allergens were used in the food enzyme manufacturing process. The Panel considered that the risk of allergic reactions upon dietary exposure to this food enzyme cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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9. Safety evaluation of the food enzyme α-amylase from the non-genetically modified Bacillus amyloliquefaciens strain AE-BAA.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano M, Sramkova M, Van Loveren H, Vernis L, Peluso S, Andryszkiewicz M, Apergi K, Cavanna D, di Piazza G, and Liu Y
- Abstract
The food enzyme α-amylase (4-α-d-glucan glucanohydrolase; EC 3.2.1.1) is produced with the non-genetically modified microorganism Bacillus amyloliquefaciens strain AE-BAA by Amano Enzyme Inc. The food enzyme is intended to be used in eight food manufacturing processes. Since residual amounts of food enzyme-total organic solids (TOS) are removed in two processes, dietary exposure was calculated only for the remaining six food manufacturing processes. It was estimated to be up to 0.842 mg TOS/kg body weight per day in European populations. The production strain of the food enzyme fulfils the requirements for the qualified presumption of safety (QPS) approach to safety assessment. Consequently, in the absence of other concerns, the Panel considered that toxicological studies were not needed for the safety assessment of this food enzyme. A search for the homology of the amino acid sequence of the food enzyme to known allergens was made and one match with a respiratory allergen was found. Known sources of food allergens were used in the manufacturing process, and the Panel considered that the risk of allergic reactions upon dietary exposure to this food enzyme cannot be excluded. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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10. Safety evaluation of the food enzyme α-amylase from the non-genetically modified Bacillus amyloliquefaciens strain UN-01.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Sanmartín L, Aguilera J, Andryszkiewicz M, Apergi K, Peluso S, di Piazza G, and Liu Y
- Abstract
The food enzyme α-amylase (4-α-d-glucan glucanohydrolase; EC 3.2.1.1) is produced with the non-genetically modified microorganism Bacillus amyloliquefaciens strain UN-01 by Nagase (Europa) GmbH. The production strain qualified for the qualified presumption of safety approach and no issues of concern arose from the production process of the food enzyme, therefore, the Panel considered that toxicological studies were unnecessary. It is intended to be used in five food manufacturing processes. Since residual amounts of total organic solids (TOS) are removed during two processes, dietary exposure was calculated only for the remaining three food manufacturing processes. It was estimated to be up to 0.434 mg TOS/kg body weight per day in European populations. A search for homology of the amino acid sequence of the food enzyme to known allergens was made and one match with a respiratory allergen was found. Known sources of food allergens were used in the food enzyme manufacturing process. The Panel considered that the risk of allergic reactions upon dietary exposure to this food enzyme cannot be excluded. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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11. Safety evaluation of an extension of use of a food enzyme containing endo-polygalacturonase, pectinesterase, pectin lyase and non-reducing end α-l-arabinofuranosidase activities from the non-genetically modified Aspergillus niger strain PEC.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Cavanna D, de Nijs RA, Di Piazza G, and Liu Y
- Abstract
The food enzyme has four declared activities: endo-polygalacturonase ((1-4)-α-d-galacturonan glycanohydrolase (endo-cleaving); EC 3.2.1.15), pectinesterase (pectin pectylhydrolase; EC 3.1.1.11), pectin lyase ((1-4)-6-O-methyl-α-d-galacturonan lyase; EC 4.2.2.10) and non-reducing end α-l-arabinofuranosidase (α-l-arabinofuranoside non-reducing end α-l-arabinofuranosidase; EC 3.2.1.55). It is produced with the non-genetically modified Aspergillus niger strain PEC by DSM Food Specialties B.V. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in three food manufacturing processes. Subsequently, the applicant has requested to extend its use to include four additional processes. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of seven food manufacturing processes. As the food enzyme-total organic solids (TOS) are removed from the final foods in one food manufacturing process, the dietary exposure to the food enzyme-TOS was estimated only for the remaining six processes. The dietary exposure was calculated to be up to 0.612 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level previously reported (204 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 333. Based on the previous evaluation, the assessment of the new data and the revised margin of exposure, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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12. Safety evaluation of the food enzyme carboxypeptidase C from the genetically modified Aspergillus niger strain PEG.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Lunardi S, Andryszkiewicz M, Criado A, and Liu Y
- Abstract
The food enzyme carboxypeptidase C (EC 3.4.16.5) is produced with the genetically modified Aspergillus niger strain PEG by DSM Food Specialties B.V. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. It is intended to be used in nine food manufacturing processes. Dietary exposure to the food enzyme-total organic solids (TOS) was estimated to be up to 2.053 mg TOS/kg body weight (bw) per day in European populations. The toxicity studies were carried out with a xylanase obtained from A. niger strain XEA. The Panel considered this food enzyme as a suitable substitute for the carboxypeptidase to be used in the toxicological studies, because both strains were derived from the same recipient strain, the location of the inserts was comparable, no partial inserts were present and the production methods were essentially the same. Genotoxicity tests did not raise a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 1850 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 901. A homology search for the amino acid sequence of the food enzyme to known allergens was made and one match with a wheat allergen was found. The Panel considered that the risk of allergic reactions by dietary exposure cannot be excluded, especially in wheat-allergic individuals, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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13. Safety evaluation of the food enzyme triacylglycerol lipase from the non-genetically modified Limtongozyma cylindracea strain AE-LAYH (B).
- Author
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Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Chesson A, Herman L, Aguilera J, Andryszkiewicz M, Criado A, Liu Y, Nielsen E, Norby K, and Zorn H
- Abstract
The food enzyme, a triacylglycerol lipase (triacylglycerol acylhydrolase; EC 3.1.1.3), is produced with the non-genetically modified Limtongozyma cylindracea strain AE-LAYH (B) by Amano Enzyme Inc. It is intended to be used in six food manufacturing processes. Since residual amounts of food enzyme-total organic solids (TOS) are removed in one process, dietary exposure was calculated only for the remaining five food manufacturing processes. It was estimated to be up to 0.315 mg TOS/kg body weight (bw) per day in European populations. As the production strain qualifies for the quality presumption of safety (QPS) approach of safety assessment and no issue of concern arising from the production process of the food enzyme were identified, the Panel considered that no toxicological studies other than the assessment of allergenicity were necessary. A homology search for the amino acid sequence of the food enzyme to those of known allergens was made and one match with a honeybee venom allergen was found. The Panel considered that a risk of allergic reactions by dietary exposure, particularly in individuals allergic to honey, cannot be excluded, but is considered to be low. Based on the data provided, the QPS status of the production strain and the absence of issues of concern arising from the food enzyme manufacturing process, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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14. Safety evaluation of the food enzyme triacylglycerol lipase from the non-genetically modified Aspergillus tubingensis strain NL151.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Chesson A, Herman L, Andryszkiewicz M, Cavanna D, Gomes A, Kovalkovičová N, Rainieri S, Di Piazza G, de Sousa RF, and Liu Y
- Abstract
The food enzyme triacylglycerol lipase (triacylglycerol acylhydrolase; EC 3.1.1.3) is produced with the non-genetically modified Aspergillus tubingensis strain NL151 by Shin Nihon Chemical Co., Ltd. The food enzyme was free from viable cells of the production organism. It is intended to be used in six food manufacturing processes. Dietary exposure was estimated to be up to 0.278 mg total organic solids (TOS)/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 1669 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 6004. A search for homology of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that, the risk of allergic reactions upon dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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15. Safety evaluation of the food enzyme endonuclease from the non-genetically modified Penicillium citrinum strain NP 11-15.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Andryszkiewicz M, Cavanna D, Criado A, Lunardi S, and Liu Y
- Abstract
The food enzyme endonuclease ( Aspergillus nuclease S
1 ; EC 3.1.30.1) is produced with the non-genetically modified Penicillium citrinum strain NP 11-15 by Shin Nihon Chemical Co., Ltd. The food enzyme is free from viable cells of the production organism. It is intended to be used in the processing of yeast and yeast products. Dietary exposure to the food enzyme-total organic solids (TOS) was estimated to be up to 0.006 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 1010 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 168,333. A search for homology of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that the risk of allergic reactions by dietary exposure cannot be excluded, especially for individuals allergic to Penicillium . However, the likelihood of such reactions will not exceed the likelihood of allergic reactions to Penicillium . Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)- Published
- 2024
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16. Safety evaluation of the food enzyme endo-1,3(4)-β-glucanase from the non-genetically modified Talaromyces versatilis strain PF8.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Chesson A, Herman L, Andryszkiewicz M, Cavanna D, Gomes A, Kovalkovičová N, de Nijs RA, di Piazza G, and Liu Y
- Abstract
The food enzyme endo-1,3(4)-β-glucanase (3-(1-3;1-4)-β-d-glucan 3(4)-glucanohydrolase; EC 3.2.1.6) is produced with the non-genetically modified Talaromyces versatilis strain PF8 by Erbslöh Geisenheim AG. The food enzyme was free from viable cells of the production organism. It is intended to be used in four food manufacturing processes. Dietary exposure to the food enzyme-total organic solids (TOS) was calculated to be up to 0.110 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 2229 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure resulted in a margin of exposure of at least 20,264. A search for homology of the amino acid sequence of the food enzyme to known allergens was made and four matches with respiratory or contact allergens were found. The Panel considered that the risk of allergic reactions upon dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
- Full Text
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17. Safety evaluation of an extension of use of the food enzyme β-glucosidase from the non-genetically modified Penicillium guanacastense strain AE-GLY.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Cavanna D, de Sousa RF, and Liu Y
- Abstract
The food enzyme β-glucosidase (β-d-glucoside glucohydrolase, EC 3.2.1.21) is produced with the non-genetically modified Penicillium guanacastense strain AE-GLY by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in four food manufacturing processes. Subsequently, the applicant has requested to extend its use to include three additional processes and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of seven food manufacturing processes. The dietary exposure was calculated to be up to 0.206 mg total organic solids (TOS)/kg body weight (bw) per day in European populations. Using the no observed adverse effect level reported in the previous opinion (943 mg TOS/kg bw per day), the Panel derived a margin of exposure of at least 4578. Based on the previous evaluation, the assessment of the new data and the revised margin of exposure, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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18. Safety evaluation of the food enzyme β -galactosidase from the genetically modified Bacillus licheniformis strain DSM 34099.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Roos Y, Andryszkiewicz M, Cavanna D, Kovalkovicova N, Peluso S, and Ferreira de Sousa R
- Abstract
The food enzyme β -galactosidase ( β -d-galactoside galactohydrolase; EC 3.2.1.23) is produced with the genetically modified Bacillus licheniformis strain DSM 34099 by Kerry Group Services International, Ltd. (KGSI). The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. The production strain met the requirements for the qualified presumption of safety (QPS) approach. The food enzyme is intended to be used in two food manufacturing processes. Dietary exposure was estimated to be up to 7.263 mg total organic solids/kg body weight per day in European populations. Given the QPS status of the production strain and the absence of concerns resulting from the food enzyme manufacturing process, toxicity tests, other than an assessment of allergenicity, were considered unnecessary by the Panel. A search for the identity of the amino acid sequence of the food enzyme to known allergens was made and one match with a food allergen from kiwi fruit was found. The Panel considered that a risk of allergic reactions upon dietary exposure to this food enzyme, particularly in individuals sensitised to kiwi fruit, cannot be excluded. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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19. Safety evaluation of the food enzyme glucan 1,4-α-maltohydrolase from the genetically modified Saccharomyces cerevisiae strain LALL-MA.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Marzo Solano ML, Sramkova M, Van Loveren H, Vernis L, Cavanna D, Fernàndez-Fraguas C, Liu Y, and Marini E
- Abstract
The food enzyme glucan 1,4-α-maltohydrolase (4-α-d-glucan α-maltohydrolase; EC 3.2.1.133) is produced with the genetically modified Saccharomyces cerevisiae strain LALL-MA+ by Danstar Ferment AG. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. It is intended to be used in the processing of cereals and other grains for production of baked products. Dietary exposure was estimated to be up to 0.014 mg TOS/kg body weight per day in European populations. Given the QPS status of the production strain and the absence of concerns resulting from the food enzyme manufacturing process, toxicity tests were considered unnecessary by the Panel. A search for the identity of the amino acid sequence of the food enzyme to known allergens was made and four matches were found, three with respiratory allergens and one with an allergen from mosquito (injected). The Panel considered that the risk of allergic reactions upon dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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20. Safety evaluation of an extension of use of the food enzyme pullulanase from the non-genetically modified Pullulanibacillus naganoensis strain AE-PL.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Cavanna D, Criado A, de Sousa RSF, Liu Y, and de Nijs RA
- Abstract
The food enzyme pullulanase (pullulan 6-α-glucanohydrolase; EC 3.2.1.41) is produced with the non-genetically modified Pullulanibacillus naganoensis strain AE-PL by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in one food manufacturing process. Subsequently, the applicant has requested to extend its use to include seven additional processes and to revise the previous use level. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of eight food manufacturing processes. As the food enzyme-total organic solids (TOS) are not carried into the final foods in two food manufacturing processes, the dietary exposure was estimated only for the remaining six processes. The dietary exposure was calculated to be up to 0.004 mg TOS/kg body weight (bw) per day in European populations. The Panel evaluated the repeated dose 90-day oral toxicity study in rats submitted in the previous application and identified a no observed adverse effect level of 643 mg TOS/kg bw per day, the highest dose tested. When compared with the calculated dietary exposure, this resulted in a margin of exposure of at least 160,750. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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21. Safety evaluation of an extension of use of the food enzyme triacylglycerol lipase from the non-genetically modified Aspergillus luchuensis strain AE-L.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Andryszkiewicz M, Cavanna D, Liu Y, de Nijs RA, and di Piazza G
- Abstract
The food enzyme triacylglycerol lipase (triacylglycerol acylhydrolase; EC 3.1.1.3) is produced with the non-genetically modified Aspergillus luchuensis strain AE-L by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in one food manufacturing process. Subsequently, the applicant has requested to extend its use to include four additional processes and to revise the previous use level. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of five food manufacturing processes. The dietary exposure to the food enzyme-total organic solids (TOS) was calculated to be up to 0.458 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level previously reported (1726 mg TOS/kg bw per day, the highest dose tested), the Panel derived a revised margin of exposure of at least 3769. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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22. Safety evaluation of a second extension of use of the food enzyme α-amylase from the non-genetically modified Cellulosimicrobium funkei strain AE-AMT.
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Cavanna D, Liu Y, de Nijs RA, and di Piazza G
- Abstract
The food enzyme α-amylase (4-α-d-glucan glucanohydrolase i.e. EC 3.2.1.1) is produced with the non-genetically modified Cellulosimicrobium funkei strain AE-AMT by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that the food enzyme did not give rise to safety concerns when used in seven food manufacturing processes. Subsequently, the applicant has requested to extend its use to include three additional processes. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of ten food manufacturing processes. As the food enzyme-total organic solids (TOS) are removed from the final foods in one food manufacturing process, the dietary exposure to the food enzyme-TOS was estimated only for the remaining nine processes. The dietary exposure was calculated to be up to 0.049 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level previously reported (230 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 4694. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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23. Safety evaluation of an extension of use of the food enzyme oryzin from the non-genetically modified Aspergillus ochraceus strain AE-P.
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Cavanna D, Liu Y, and di Piazza G
- Abstract
The food enzyme oryzin (EC 3.4.21.63) is produced with the non-genetically modified Aspergillus ochraceus strain AE-P by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in nine food manufacturing processes. Subsequently, the applicant has requested to extend its use to one additional process, to withdraw two food processes and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of eight food manufacturing processes. The dietary exposure to the food enzyme-total organic solids (TOS) was calculated to be up to 0.354 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level reported in the previous opinion (1862 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 5260. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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24. Safety evaluation of an extension of use of the food enzyme triacylglycerol lipase from the non-genetically modified Rhizopus arrhizus strain AE-TL(B).
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Cavanna D, Liu Y, and Ferreira de Sousa R
- Abstract
The food enzyme triacylglycerol lipase (triacylglycerol acylhydrolase; EC 3.1.1.3) is produced with the non-genetically modified Rhizopus arrhizu s strain AE-TL(B) by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in two food manufacturing processes. Subsequently, the applicant requested to extend its use to include four additional processes and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme when used in a total of six food manufacturing processes. As the food enzyme-total organic solids (TOS) are removed from one food manufacturing process, the dietary exposure to the food enzyme-TOS was estimated only for the remaining five processes. Dietary exposure was calculated to be up to 0.086 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level reported in the previous opinion (1960 mg TOS/kg bw per day, the highest dose tested), the Panel derived a margin of exposure of at least 22,791. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use., Competing Interests: If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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25. Safety evaluation of an extension of use of the food enzyme thermolysin from the non-genetically modified Anoxybacillus caldiproteolyticus strain AE-TP.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Cavanna D, Liu Y, and di Piazza G
- Abstract
The food enzyme thermolysin (EC. 3.4.24.27) is produced with the non-genetically modified Anoxybacillus caldiproteolyticus strain AE-TP by Amano Enzyme Inc. A safety evaluation of this food enzyme was made previously, in which EFSA concluded that this food enzyme did not give rise to safety concerns when used in eight food manufacturing processes. Subsequently, the applicant has requested to extend its use to one additional process, to withdraw two processes and to revise the use levels. In this assessment, EFSA updated the safety evaluation of this food enzyme for use in a total of seven food manufacturing processes. The dietary exposure to the food enzyme-total organic solids (TOS) was calculated to be up to 0.989 mg TOS/kg body weight (bw) per day in European populations. When combined with the no observed adverse effect level reported in the previous opinion (700 mg TOS/kg bw per day, the mid-dose tested), the Panel derived a revised margin of exposure of at least 708. Based on the data provided for the previous evaluation and the revised margin of exposure in the present evaluation, the Panel concluded that this food enzyme does not give rise to safety concerns under the revised intended conditions of use., Competing Interests: The Panel wishes to thank the following for the support provided to this scientific output: Andrew ChessonIf you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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26. Safety evaluation of the food enzyme lysophospholipase from the genetically modified Trichoderma reesei strain DP-Nyc81.
- Author
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Zorn H, Barat Baviera JM, Bolognesi C, Catania F, Gadermaier G, Greiner R, Mayo B, Mortensen A, Roos YH, Solano MLM, Sramkova M, Van Loveren H, Vernis L, Andryszkiewicz M, Liu Y, and Lunardi S
- Abstract
The food enzyme lysophospholipase (2-lysophosphatidylcholine acylhydrolase, EC 3.1.1.5) is produced with the genetically modified Trichoderma reesei strain DP-Nyc81 by Genencor International B.V. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. It is intended to be used in the processing of cereals and other grains for the production of glucose syrups and other starch hydrolysates. Since residual amounts of food enzyme-total organic solids are removed during these food manufacturing processes, dietary exposure was not calculated and toxicological studies were considered unnecessary. A search for the identity of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that the risk of allergic reactions upon dietary exposure cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use., Competing Interests: The FEZ Panel wishes to thank the following for the support provided to this scientific output: Andrew Chesson and Pier Sandro Cocconcelli.If you wish to access the declaration of interests of any expert contributing to an EFSA scientific assessment, please contact interestmanagement@efsa.europa.eu., (© 2024 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)
- Published
- 2024
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27. Nanocomposite hydrogels in skin cancer medicine.
- Author
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Balintova L, Blazickova M, and Sramkova M
- Subjects
- Humans, Drug Delivery Systems, Nanocomposites therapeutic use, Nanocomposites chemistry, Antineoplastic Agents therapeutic use, Skin Neoplasms drug therapy, Hydrogels chemistry
- Abstract
Skin cancer is one of the most common malignancies in white populations. The therapy strategy is important in skin cancer treatment, depending on several criteria such as stage, size, and localization. Removal of cancerous tissue following anticancer therapeutic administration is considered as gold standard in skin cancer treatment. However, annually rising drug resistance, local inflammation, and ineffective treatment result in a reduction in the effectiveness of the patient's treatment. Nanotechnology has emerged as a prospective in the field of skin cancer medicine, offering innovative, promising solutions for therapeutic procedures and targeted drug delivery. Different nanomaterials are investigated for their potential in skin cancer treatment. Nanohydrogels as a hybrid material, have gained considerable attention due to their unique biomedical and pharmaceutical properties, such as biocompatibility, high water content, and tunable physicochemical characteristics. The principal problem with common skin melanoma chemotherapy is the strong side effects because therapeutics used for treatment do not distinguish cancer cells from healthy cells. Nanohydrogels, as a new-generation, versatile system with the possession of dual characteristics of hydrogels and nanoparticles have shown great potential in targeted delivery in cancer therapy thanks to the possibility of their various modifications, and by that overcome problems with side effects of treatment. This scientific review provides an analysis of the current state of research on nanohydrogels in skin cancer medicine, highlighting their design principles, synthesis methods, and applications in drug delivery, imaging, and combination therapies.
- Published
- 2024
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- View/download PDF
28. Genome-wide DNA methylome and transcriptome changes induced by inorganic nanoparticles in human kidney cells after chronic exposure.
- Author
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Soltysova A, Begerova P, Jakic K, Kozics K, Sramkova M, Meese E, Smolkova B, and Gabelova A
- Subjects
- Humans, Epigenome genetics, Gold, DNA Methylation genetics, Kidney, Transcriptome genetics, Metal Nanoparticles toxicity
- Abstract
The unique physicochemical properties make inorganic nanoparticles (INPs) an exciting tool in diagnosis and disease management. However, as INPs are relatively difficult to fully degrade and excrete, their unintended accumulation in the tissue might result in adverse health effects. Herein, we provide a methylome-transcriptome framework for chronic effects of INPs, commonly used in biomedical applications, in human kidney TH-1 cells. Renal clearance is one of the most important routes of nanoparticle excretion; therefore, a detailed evaluation of nanoparticle-mediated nephrotoxicity is an important task. Integrated analysis of methylome and transcriptome changes induced by INPs (PEG-AuNPs, Fe
3 O4 NPs, SiO2 NPs, and TiO2 NPs) revealed significantly deregulated genes with functional classification in immune response, DNA damage, and cancer-related pathways. Although most deregulated genes were unique to individual INPs, a relatively high proportion of them encoded the transcription factors. Interestingly, FOS hypermethylation inversely correlating with gene expression was associated with all INPs exposures. Our study emphasizes the need for a more comprehensive investigation of INPs' biological safety, especially after chronic exposure., (© 2021. The Author(s).)- Published
- 2023
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29. Rapid identification of in vitro cell toxicity using an electrochemical membrane screening platform.
- Author
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Kohl Y, William N, Elje E, Backes N, Rothbauer M, Srancikova A, Rundén-Pran E, El Yamani N, Korenstein R, Madi L, Barbul A, Kozics K, Sramkova M, Steenson K, Gabelova A, Ertl P, Dusinska M, and Nelson A
- Subjects
- Humans, Cell Line, Chlorpromazine, Hazardous Substances, Phospholipids, Toxicity Tests methods, Liver
- Abstract
This study compares the performance and output of an electrochemical phospholipid membrane platform against respective in vitro cell-based toxicity testing methods using three toxicants of different biological action (chlorpromazine (CPZ), colchicine (COL) and methyl methanesulphonate (MMS)). Human cell lines from seven different tissues (lung, liver, kidney, placenta, intestine, immune system) were used to validate this physicochemical testing system. For the cell-based systems, the effective concentration at 50 % cell death (EC
50 ) values are calculated. For the membrane sensor, a limit of detection (LoD) value was extracted as a quantitative parameter describing the minimum concentration of toxicant which significantly affects the structure of the phospholipid sensor membrane layer. LoD values were found to align well with the EC50 values when acute cell viability was used as an end-point and showed a similar toxicity ranking of the tested toxicants. Using the colony forming efficiency (CFE) or DNA damage as end-point, a different order of toxicity ranking was observed. The results of this study showed that the electrochemical membrane sensor generates a parameter relating to biomembrane damage, which is the predominant factor in decreasing cell viability when in vitro models are acutely exposed to toxicants. These results lead the way to using electrochemical membrane-based sensors for rapid relevant preliminary toxicity screens., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)- Published
- 2023
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30. Pharmacokinetics of PEGylated Gold Nanoparticles: In Vitro-In Vivo Correlation.
- Author
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Dubaj T, Kozics K, Sramkova M, Manova A, Bastús NG, Moriones OH, Kohl Y, Dusinska M, Runden-Pran E, Puntes V, Nelson A, Gabelova A, and Simon P
- Abstract
Data suitable for assembling a physiologically-based pharmacokinetic (PBPK) model for nanoparticles (NPs) remain relatively scarce. Therefore, there is a trend in extrapolating the results of in vitro and in silico studies to in vivo nanoparticle hazard and risk assessment. To evaluate the reliability of such approach, a pharmacokinetic study was performed using the same polyethylene glycol-coated gold nanoparticles (PEG-AuNPs) in vitro and in vivo. As in vitro models, human cell lines TH1, A549, Hep G2, and 16HBE were employed. The in vivo PEG-AuNP biodistribution was assessed in rats. The internalization and exclusion of PEG-AuNPs in vitro were modeled as first-order rate processes with the partition coefficient describing the equilibrium distribution. The pharmacokinetic parameters were obtained by fitting the model to the in vitro data and subsequently used for PBPK simulation in vivo. Notable differences were observed in the internalized amount of Au in individual cell lines compared to the corresponding tissues in vivo, with the highest found for renal TH1 cells and kidneys. The main reason for these discrepancies is the absence of natural barriers in the in vitro conditions. Therefore, caution should be exercised when extrapolating in vitro data to predict the in vivo NP burden and response to exposure.
- Published
- 2022
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31. Pharmacokinetics, Biodistribution, and Biosafety of PEGylated Gold Nanoparticles In Vivo.
- Author
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Kozics K, Sramkova M, Kopecka K, Begerova P, Manova A, Krivosikova Z, Sevcikova Z, Liskova A, Rollerova E, Dubaj T, Puntes V, Wsolova L, Simon P, Tulinska J, and Gabelova A
- Abstract
Despite the obvious advantages of gold nanoparticles for biomedical applications, controversial and incomplete toxicological data hamper their widespread use. Here, we present the results from an in vivo toxicity study using gold nanoparticles coated with polyethylene glycol (PEG-AuNPs). The pharmacokinetics and biodistribution of PEG-AuNPs were examined in the rat's liver, lung, spleen, and kidney after a single i.v. injection (0.7 mg/kg) at different time intervals. PEG-AuNPs had a relatively long blood circulation time and accumulated primarily in the liver and spleen, where they remained for up to 28 days after administration. Increased cytoplasmic vacuolation in hepatocytes 24 h and 7 days after PEG-AuNPs exposure and apoptotic-like cells in white splenic pulp 24 h after administration has been detected, however, 28 days post-exposure were no longer observed. In contrast, at this time point, we identified significant changes in lipid metabolism, altered levels of liver injury markers, and elevated monocyte count, but without marked biological relevance. In blood cells, no DNA damage was present in any of the studied time intervals, with the exception of DNA breakage transiently detected in primary kidney cells 4 h post-injection. Our results indicate that the tissue accumulation of PEG-AuNPs might result in late toxic effects.
- Published
- 2021
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32. Minimum Information for Reporting on the Comet Assay (MIRCA): recommendations for describing comet assay procedures and results.
- Author
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Møller P, Azqueta A, Boutet-Robinet E, Koppen G, Bonassi S, Milić M, Gajski G, Costa S, Teixeira JP, Costa Pereira C, Dusinska M, Godschalk R, Brunborg G, Gutzkow KB, Giovannelli L, Cooke MS, Richling E, Laffon B, Valdiglesias V, Basaran N, Del Bo' C, Zegura B, Novak M, Stopper H, Vodicka P, Vodenkova S, de Andrade VM, Sramkova M, Gabelova A, Collins A, and Langie SAS
- Subjects
- Comet Assay standards, Consensus, Guideline Adherence statistics & numerical data, Humans, Laboratories, Comet Assay methods, Research Design
- Abstract
The comet assay is a widely used test for the detection of DNA damage and repair activity. However, there are interlaboratory differences in reported levels of baseline and induced damage in the same experimental systems. These differences may be attributed to protocol differences, although it is difficult to identify the relevant conditions because detailed comet assay procedures are not always published. Here, we present a Consensus Statement for the Minimum Information for Reporting Comet Assay (MIRCA) providing recommendations for describing comet assay conditions and results. These recommendations differentiate between 'desirable' and 'essential' information: 'essential' information refers to the precise details that are necessary to assess the quality of the experimental work, whereas 'desirable' information relates to technical issues that might be encountered when repeating the experiments. Adherence to MIRCA recommendations should ensure that comet assay results can be easily interpreted and independently verified by other researchers.
- Published
- 2020
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33. Comet assay in neural cells as a tool to monitor DNA damage induced by chemical or physical factors relevant to environmental and occupational exposure.
- Author
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Kruszewski M, Sikorska K, Meczynska-Wielgosz S, Grzelak A, Sramkova M, Gabelova A, and Kapka-Skrzypczak L
- Subjects
- Animals, Cell Line, Tumor, Environmental Pollutants toxicity, Female, Flame Retardants toxicity, Glioblastoma pathology, Humans, Magnetic Fields adverse effects, Male, Mice, Nanoparticles toxicity, Neuroblastoma pathology, Neurons chemistry, Occupational Exposure, Pesticides toxicity, Pheochromocytoma pathology, Rats, Research Design, Biological Monitoring methods, Comet Assay methods, DNA Damage, Environmental Exposure, Neurons drug effects, Xenobiotics toxicity
- Abstract
Biomonitoring of the effects of environmental and occupational exposure relevant chemical or physical factors on central nervous system is difficult due to the problems with sampling of biological material. Thus, surrogate systems allowing for the estimation of effect intensity are necessary to evaluate a potential risk of exposure. Cancerous neural cells in culture seem to be a reliable trustworthy alternative to ex vivo primary cells culture, where brain tissue is hardly available. In this review we summarized attempts to test genotoxicity of environmentally related xenobiotics or physical factors. Different neural cells of human and non-human origin are described in respect to their use in genotoxicity testing using the comet assay. Surprisingly, despite the large number of commercially available neural cells of different type and origin, only twelve were used for genotoxicity testing by the comet assay. We also recapitulate the environmentally relevant chemical and physical factors tested on neural cell lines in vitro by the comet assay. The most prevalent were fire retardants, plant protection agents, nanoparticles and magnetic field., (Copyright © 2018. Published by Elsevier B.V.)
- Published
- 2019
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34. Nephrotoxicity: Topical issue.
- Author
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Gabelova A, Kozics K, Kapka-Skrzypczak L, Kruszewski M, and Sramkova M
- Subjects
- Animals, Automation, Cell Line, DNA Damage, Drug Development, Drug Evaluation, Preclinical methods, Forecasting, Guidelines as Topic, HEK293 Cells, Humans, Image Processing, Computer-Assisted, Kidney cytology, Miniaturization, Nanostructures toxicity, Reproducibility of Results, Risk Assessment, Single-Cell Analysis methods, Th1 Cells, Comet Assay methods, Kidney drug effects, Toxicity Tests methods
- Abstract
Drug-induced kidney injury is one of the most significant adverse events and dose limiting factor in chemotherapy as well a major cause of prospective drug attrition during pharmaceutical development. Moreover, kidney injury can also occur as a consequence of exposures to environmental xenobiotics such as heavy metals, fungal toxins and nanomaterials. The lack of adequate in vitro human kidney models that mimic more realistically the in vivo conditions and the absence of suitable and robust, cost-effective and predictive cell-based in vitro assays contribute to an underestimation of the kidney toxic potential of new drugs and xenobiotics. Therefore, a rapid screening system capable to detect potential nephrotoxicity at early stages of drug discovery is an urgent need. Here we provide an overview of human cell lines currently used as a surrogate in vitro kidney models in nephrotoxicity studies, including their advantages and limitations. In addition, the capacity of the single cell gel electrophoresis (SCGE)/comet assay as a potential tool in kidney toxicants screening is discussed. Despite a limited number of studies using the comet assay to evaluate the drug-induced kidney damage potential, a considerable variability in SCGE methodology (e.g. lysis, unwinding, and electrophoresis conditions) has been observed. Before the comet assay can be included in nephrotoxicity testing, a basic guideline has to be developed. To test its feasibility, additional in vitro experiments including inter-laboratory validation studies based on this guideline have to be performed., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2019
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35. Kidney nanotoxicity studied in human renal proximal tubule epithelial cell line TH1.
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Sramkova M, Kozics K, Masanova V, Uhnakova I, Razga F, Nemethova V, Mazancova P, Kapka-Skrzypczak L, Kruszewski M, Novotova M, Puntes VF, and Gabelova A
- Subjects
- Comet Assay, DNA Breaks, DNA Damage, Dynamic Light Scattering, Gold toxicity, Humans, Kidney Tubules, Proximal cytology, Magnetite Nanoparticles toxicity, Oxidative Stress, Phagocytosis, Rheology, Silicon Dioxide toxicity, Single-Cell Analysis, Time Factors, Titanium toxicity, Epithelial Cells drug effects, Kidney Tubules, Proximal drug effects, Metal Nanoparticles toxicity, Th1 Cells drug effects
- Abstract
Progressive expansion of nanomaterials in our everyday life raises concerns about their safety for human health. Although kidneys are the primary organs of xenobiotic elimination, little attention has been paid to the kidneys in terms of nanotoxicological studies up to now. Here we investigate the cytotoxic and genotoxic potential of four solid-core uncoated inorganic nanoparticles (TiO
2 NPs, SiO2 NPs, Fe3 O4 NPs and AuNPs) using the human renal proximal tubule epithelial TH1 cells. To mimic the in vivo conditions more realistic, TH1 cells were exposed in vitro to inorganic NPs under static as well as dynamic conditions for 3 h and 24 h. The medium throughput alkaline comet assay (12 minigels per slide) was employed to evaluate the impact of these NPs on genome integrity and their capacity to produce oxidative lesions to DNA. The accumulation and localization of studied inorganic NPs inside the cells was monitored by transmission electron microscopy (TEM) and the efficacy of internalization of particular NPs was determined by atomic absorption spectroscopy (AAS) and inductively coupled plasma mass spectrometry (ICP-MS). From all the tested NPs, only Fe3 O4 NPs induced a slight cytotoxicity in TH1 cells exposed to high concentrations (>700 μg/ml) for 24 h. On the other hand, the inorganic NPs did not increase significantly the level of DNA strand breaks or oxidative DNA damage regardless of the treatment mode (static vs. dynamic conditions). Interestingly, substantial differences were observed in the internalized amount of inorganic NPs in TH1 cells exposed to equivalent (2.2 μg/ml) concentration. Fe3 O4 NPs were most efficiently taken up while the lowest quantity of particles was determined in TiO2 NPs-treated cells. As the particle size and shape of individual inorganic NPs in culture medium was nearly identical, it is reasonable to suppose that the chemical composition may contribute to the differences in the efficacy of NPs uptake., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)- Published
- 2019
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36. Assessment of DNA damage in Polish children environmentally exposed to pesticides.
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Kapka-Skrzypczak L, Czajka M, Sawicki K, Matysiak-Kucharek M, Gabelova A, Sramkova M, Bartyzel-Lechforowicz H, and Kruszewski M
- Subjects
- Acetylcholinesterase blood, Biological Monitoring methods, Child, Cholinesterase Inhibitors toxicity, Comet Assay, DNA blood, DNA drug effects, DNA Breaks, DNA-Formamidopyrimidine Glycosylase pharmacology, Female, Food Contamination, Guanine analogs & derivatives, Guanine blood, Humans, Male, Micronucleus Tests, Parents, Poland, Rural Population, DNA Damage, Environmental Exposure, Pesticides toxicity
- Abstract
Exposure to pesticides leads to complex, long-lasting adverse effects on human health, and poses a substantial risk to those living in areas devoted to agriculture. Children are particularly vulnerable to the pesticide exposure, due to the developmental, dietary and physiological factors. Small body mass and typical exploratory behavior result in increased risk of intoxication. Thus, even exposure to low concentrations of pesticides, if of sufficient duration, may lead to permanent health disorders and limit their harmonious development. In this study 108 children, living in areas of an intense pesticide use and a control group (n = 92) of children from an agrotouristic area were investigated, whether DNA damage increased due to prolonged pesticide exposure. A presence of DNA breaks and oxidative damage to DNA bases, characterized as Fpg-sensitive sites, were detected by comet assay. Micronuclei (MN) formation was evaluated by cytokinesis-block MN assay. The exposure of children to pesticides resulted in increased number of MN in peripheral blood lymphocytes (P = 0.016), increased DNA strand breaks level (P = 0.002) and oxidative damage to DNA (P < 0.001). Negative correlation was demonstrated between the level of DNA strand breaks and acetylcholinesterase (AChE) activity in exposed group. In conclusion, despite just environmental pesticide exposure in the test group of children, significant biological effects were detected., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
37. The comet assay in animal models: From bugs to whales - (Part 2 Vertebrates).
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Gajski G, Žegura B, Ladeira C, Novak M, Sramkova M, Pourrut B, Del Bo' C, Milić M, Gutzkow KB, Costa S, Dusinska M, Brunborg G, and Collins A
- Subjects
- Animals, DNA Damage drug effects, Environmental Monitoring methods, Humans, Models, Animal, Vertebrates, Whales, Comet Assay methods
- Abstract
The comet assay has become one of the methods of choice for the evaluation and measurement of DNA damage. It is sensitive, quick to perform and relatively affordable for the evaluation of DNA damage and repair at the level of individual cells. The comet assay can be applied to virtually any cell type derived from different organs and tissues. Even though the comet assay is predominantly used on human cells, the application of the assay for the evaluation of DNA damage in yeast, plant and animal cells is also quite high, especially in terms of biomonitoring. The present extensive overview on the usage of the comet assay in animal models will cover both terrestrial and water environments. The first part of the review was focused on studies describing the comet assay applied in invertebrates. The second part of the review, (Part 2) will discuss the application of the comet assay in vertebrates covering cyclostomata, fishes, amphibians, reptiles, birds and mammals, in addition to chordates that are regarded as a transitional form towards vertebrates. Besides numerous vertebrate species, the assay is also performed on a range of cells, which includes blood, liver, kidney, brain, gill, bone marrow and sperm cells. These cells are readily used for the evaluation of a wide spectrum of genotoxic agents both in vitro and in vivo. Moreover, the use of vertebrate models and their role in environmental biomonitoring will also be discussed as well as the comparison of the use of the comet assay in vertebrate and human models in line with ethical principles. Although the comet assay in vertebrates is most commonly used in laboratory animals such as mice, rats and lately zebrafish, this paper will only briefly review its use regarding laboratory animal models and rather give special emphasis to the increasing usage of the assay in domestic and wildlife animals as well as in various ecotoxicological studies., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
38. The comet assay in animal models: From bugs to whales - (Part 1 Invertebrates).
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Gajski G, Žegura B, Ladeira C, Pourrut B, Del Bo' C, Novak M, Sramkova M, Milić M, Gutzkow KB, Costa S, Dusinska M, Brunborg G, and Collins A
- Subjects
- Animals, Comet Assay methods, DNA Damage genetics, Humans, Models, Animal, Invertebrates genetics, Whales genetics
- Abstract
The comet assay, also called single cell gel electrophoresis, is a sensitive, rapid and low-cost technique for quantifying and analysing DNA damage and repair at the level of individual cells. The assay itself can be applied on virtually any cell type derived from different organs and tissues of eukaryotic organisms. Although it is mainly used on human cells, the assay has applications also in the evaluation of DNA damage in yeast, plant and animal cells. Therefore, the purpose of this review is to give an extensive overview on the usage of the comet assay in animal models from invertebrates to vertebrates, covering both terrestrial and water biota. The comet assay is used in a variety of invertebrate species since they are regarded as interesting subjects in ecotoxicological research due to their significance in ecosystems. Hence, the first part of the review (Part 1) will discuss the application of the comet assay in invertebrates covering protozoans, platyhelminthes, planarians, cnidarians, molluscs, annelids, arthropods and echinoderms. Besides a large number of animal species, the assay is also performed on a variety of cells, which includes haemolymph, gills, digestive gland, sperm and embryo cells. The mentioned cells have been used for the evaluation of a broad spectrum of genotoxic agents both in vitro and in vivo. Moreover, the use of invertebrate models and their role from an ecotoxicological point of view will also be discussed as well as the comparison of the use of the comet assay in invertebrate and human models. Since the comet assay is still developing, its increasing potential in assessing DNA damage in animal models is crucial especially in the field of ecotoxicology and biomonitoring at the level of different species, not only humans., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
39. Antioxidant potential of essential oil from Lavandula angustifolia in in vitro and ex vivo cultured liver cells.
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Kozics K, Srancikova A, Sedlackova E, Horvathova E, Melusova M, Melus V, Krajcovicova Z, and Sramkova M
- Subjects
- Animals, Cells, Cultured, Glutathione metabolism, Glutathione Peroxidase metabolism, Hep G2 Cells, Humans, Liver, Oxidative Stress, Plant Oils pharmacology, Rats, Superoxide Dismutase metabolism, Antioxidants pharmacology, Hepatocytes drug effects, Lavandula chemistry, Oils, Volatile pharmacology
- Abstract
Lavender is a commonly used herb in traditional medicine in Asia and Europe. It has been reported to be an effective medical plant in treating inflammation, depression and stress, thanks to its sedative and anxiolytic action, thrombotic, and antimicrobial properties. In the present study we investigated the protective effects of essential oil from Lavandula angustifolia (LO) against hydrogen peroxide and tert-butyl hydroperoxide -induced DNA damage. Also the effects of LO on the levels of enzymatic and non-enzymatic antioxidants (SOD-superoxide dismutase, GPx-glutathione peroxidase, GSH-glutathione) were evaluated in in vitro (human hepatoma cell line HepG2) and in ex vivo (freshly isolated rat hepatocytes) systems. The results showed that the oxidant-induced DNA lesions were significantly reduced in both systems pre-treated with the Lavandula angustifolia. The observed DNA-protective activity could be explained by both elevation of GPx activity in cells pre-treated with LO and antioxidant activity of LO.
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- 2017
- Full Text
- View/download PDF
40. Polyethylenimine-mediated expression of transgenes in the acinar cells of rats salivary glands in vivo.
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Sramkova M, Parente L, Wigand T, Aye MP, Shitara A, and Weigert R
- Abstract
Non viral-mediated transfection of plasmid DNA provides a fast and reliable way to express various transgenes in selected cell populations in live animals. Here, we show an improvement of a previously published method that is based on injecting plasmid DNA into the ductal system of the salivary glands in live rats. Specifically, using complexes between plasmid DNA and polyethyleneimine (PEI) we show that the expression of the transgenes is directed selectively to the salivary acinar cells. PEI does not affect the ability of cells to undergo regulated exocytosis, which was one of the main drawbacks of the previous methods. Moreover PEI does not affect the proper localization and targeting of transfected proteins, as shown for the apical plasma membrane water channel aquaporin 5 (AQP5). Overall, this approach, coupled with the use of intravital microscopy, permits to conduct localization and functional studies under physiological conditions, in a rapid, reliable, and affordable fashion.
- Published
- 2015
- Full Text
- View/download PDF
41. Intravital microscopy to image membrane trafficking in live rats.
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Masedunskas A, Sramkova M, Parente L, and Weigert R
- Subjects
- Animals, Exocytosis, Fluorescent Dyes chemistry, Gene Transfer Techniques, Microscopy, Confocal, Rats, Rats, Sprague-Dawley, Restraint, Physical instrumentation, Staining and Labeling, Time-Lapse Imaging, Endocytosis, Submandibular Gland cytology
- Abstract
Intravital microscopy is a powerful tool that enables imaging various biological processes in live animals. Here, we describe a series of procedures designed to image subcellular structures, such as endosomes and secretory vesicles in the salivary glands (SGs) of live rats. To this aim, we used fluorescently labeled molecules and/or fluorescently tagged proteins that were transiently transfected in the live animal.
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- 2013
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42. Intravital microscopy: a practical guide on imaging intracellular structures in live animals.
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Masedunskas A, Milberg O, Porat-Shliom N, Sramkova M, Wigand T, Amornphimoltham P, and Weigert R
- Subjects
- Animals, Actin Cytoskeleton, Microscopy methods, Organelles
- Abstract
Intravital microscopy is an extremely powerful tool that enables imaging several biological processes in live animals. Recently, the ability to image subcellular structures in several organs combined with the development of sophisticated genetic tools has made possible extending this approach to investigate several aspects of cell biology. Here we provide a general overview of intravital microscopy with the goal of highlighting its potential and challenges. Specifically, this review is geared toward researchers that are new to intravital microscopy and focuses on practical aspects of carrying out imaging in live animals. Here we share the know-how that comes from first-hand experience, including topics such as choosing the right imaging platform and modality, surgery and stabilization techniques, anesthesia and temperature control. Moreover, we highlight some of the approaches that facilitate subcellular imaging in live animals by providing numerous examples of imaging selected organelles and the actin cytoskeleton in multiple organs.
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- 2012
- Full Text
- View/download PDF
43. Plasmid DNA is internalized from the apical plasma membrane of the salivary gland epithelium in live animals.
- Author
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Sramkova M, Masedunskas A, and Weigert R
- Subjects
- Acinar Cells, Adenoviridae genetics, Animals, Endocytosis, Epithelium metabolism, Gene Transfer Techniques, Genetic Vectors, Male, Plasmids, Rats, Rats, Sprague-Dawley, Submandibular Gland metabolism, Transgenes, Cell Membrane metabolism, DNA metabolism, Salivary Glands metabolism
- Abstract
Non-viral-mediated gene delivery represents an alternative way to express the gene of interest without inducing immune responses or other adverse effects. Understanding the mechanisms by which plasmid DNAs are delivered to the proper target in vivo is a fundamental issue that needs to be addressed in order to design more effective strategies for gene therapy. As a model system, we have used the submandibular salivary glands in live rats and we have recently shown that reporter transgenes can be expressed in different cell populations of the glandular epithelium, depending on the modality of administration of plasmid DNA. Here, by using a combination of immunofluorescence and intravital microscopy, we have explored the relationship between the pattern of transgenes expression and the internalization of plasmid DNA. We found that plasmid DNA is internalized: (1) by all the cells in the salivary gland epithelium, when administered alone, (2) by large ducts, when mixed with empty adenoviral particles, and (3) by acinar cells upon stimulation of compensatory endocytosis. Moreover, we showed that plasmid DNA utilizes different routes of internalization, and evades both the lysosomal degradative pathway and the retrograde pathway towards the Golgi apparatus. This study clearly shows that in vivo approaches have the potential to address fundamental questions on the cellular mechanisms regulating gene delivery.
- Published
- 2012
- Full Text
- View/download PDF
44. Homeostasis of the apical plasma membrane during regulated exocytosis in the salivary glands of live rodents.
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Masedunskas A, Sramkova M, and Weigert R
- Abstract
In exocrine organs such as the salivary glands, fluids and proteins are secreted into ductal structures by distinct mechanisms that are tightly coupled. In the acinar cells, the major secretory units of the salivary glands, fluids are secreted into the acinar canaliculi through paracellular and intracellular transport, whereas proteins are stored in large granules that undergo exocytosis and fuse with the apical plasma membranes releasing their content into the canaliculi. Both secretory processes elicit a remodeling of the apical plasma membrane that has not been fully addressed in in vitro or ex vivo models. Recently, we have studied regulated exocytosis in the salivary glands of live rodents, focusing on the role that actin and myosin plays in this process. We observed that during exocytosis both secretory granules and canaliculi are subjected to the hydrostatic pressure generated by fluid secretion. Furthermore, the absorption of the membranes of the secretory granules contributes to the expansion and deformation of the canaliculi. Here we suggest that the homeostasis of the apical plasma membranes during exocytosis is maintained by various strategies that include: (1) membrane retrieval via compensatory endocytosis, (2) increase of the surface area via membrane folds and (3) recruitment of a functional actomyosin complex. Our observations underscore the important relationship between tissue architecture and cellular response, and highlight the potential of investigating biological processes in vivo by using intravital microscopy.
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- 2011
- Full Text
- View/download PDF
45. Role for the actomyosin complex in regulated exocytosis revealed by intravital microscopy.
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Masedunskas A, Sramkova M, Parente L, Sales KU, Amornphimoltham P, Bugge TH, and Weigert R
- Subjects
- Actins metabolism, Adrenergic beta-Agonists pharmacology, Animals, Cell Membrane, Cell Polarity, Mice, Mice, Transgenic, Nonmuscle Myosin Type IIA, Protein Transport, Salivary Glands, Secretory Vesicles metabolism, Actomyosin physiology, Exocytosis drug effects, Microscopy, Confocal
- Abstract
The regulation and the dynamics of membrane trafficking events have been studied primarily in in vitro models that often do not fully reflect the functional complexity found in a living multicellular organism. Here we used intravital microscopy in the salivary glands of live rodents to investigate regulated exocytosis, a fundamental process in all of the secretory organs. We found that β-adrenergic stimulation elicits exocytosis of large secretory granules, which gradually collapse with the apical plasma membrane without any evidence of compound exocytosis, as was previously described. Furthermore, we show that the driving force required to complete the collapse of the granules is provided by the recruitment of F-actin and nonmuscle myosin II on the granule membranes that is triggered upon fusion with the plasma membrane. Our results provide information on the machinery controlling regulated secretion and show that intravital microscopy provides unique opportunities to address fundamental questions in cell biology under physiological conditions.
- Published
- 2011
- Full Text
- View/download PDF
46. Intravital microscopy: a novel tool to study cell biology in living animals.
- Author
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Weigert R, Sramkova M, Parente L, Amornphimoltham P, and Masedunskas A
- Subjects
- Animals, Cell Biology, Microscopy trends, Microscopy, Fluorescence methods, Microscopy, Fluorescence trends, Animal Structures cytology, Cells cytology, Cytological Techniques methods, Microscopy methods
- Abstract
Intravital microscopy encompasses various optical microscopy techniques aimed at visualizing biological processes in live animals. In the last decade, the development of non-linear optical microscopy resulted in an enormous increase of in vivo studies, which have addressed key biological questions in fields such as neurobiology, immunology and tumor biology. Recently, few studies have shown that subcellular processes can be imaged dynamically in the live animal at a resolution comparable to that achieved in cell cultures, providing new opportunities to study cell biology under physiological conditions. The overall aim of this review is to give the reader a general idea of the potential applications of intravital microscopy with a particular emphasis on subcellular imaging. An overview of some of the most exciting studies in this field will be presented using resolution as a main organizing criterion. Indeed, first we will focus on those studies in which organs were imaged at the tissue level, then on those focusing on single cells imaging, and finally on those imaging subcellular organelles and structures.
- Published
- 2010
- Full Text
- View/download PDF
47. Expression of plasmid DNA in the salivary gland epithelium: novel approaches to study dynamic cellular processes in live animals.
- Author
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Sramkova M, Masedunskas A, Parente L, Molinolo A, and Weigert R
- Subjects
- Adaptation, Physiological, Adenoviridae classification, Animals, Biomarkers metabolism, Cell Physiological Phenomena, Endocytosis physiology, Epithelium metabolism, Epithelium virology, Exocytosis drug effects, Fluorescent Dyes pharmacokinetics, Intracellular Space metabolism, Isoproterenol pharmacology, Male, Rats, Rats, Sprague-Dawley, Submandibular Gland cytology, Submandibular Gland physiology, Submandibular Gland virology, Tissue Distribution, Virion, Virus Replication, DNA metabolism, Physiology methods, Physiology trends, Plasmids metabolism, Submandibular Gland metabolism
- Abstract
The ability to dynamically image cellular and subcellular structures in a live animal and to target genes to a specific cell population in a living tissue provides a unique tool to address many biological questions in the proper physiological context. Here, we describe a powerful approach that is based on the use of rat submandibular salivary glands, which offer the possibility to easily perform intravital imaging and deliver molecules from the oral cavity, and plasmid DNA, which offers the advantage of rapid manipulations. We show that, under different experimental conditions, a reporter molecule can be rapidly expressed in specific compartments of the glands: 1) in the intercalated ducts, when plasmid DNA is administered alone, and 2) in granular ducts, striated ducts, and, to a lesser extent, acini, when plasmid DNA is mixed with replication-deficient adenovirus subtype 5 particles. Remarkably, we also found that gene expression can be directed to acinar cells when plasmid DNA is administered during isoproterenol-stimulated exocytosis, suggesting a novel mechanism of plasmid internalization regulated by compensatory endocytosis. Finally, as a practical application of these strategies, we show how the expression of fluorescently tagged molecules enables the study of the dynamics of various organelles in live animals at a resolution comparable to that achieved in cell cultures.
- Published
- 2009
- Full Text
- View/download PDF
48. The effect of hypusine modification on the intracellular localization of eIF5A.
- Author
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Lee SB, Park JH, Kaevel J, Sramkova M, Weigert R, and Park MH
- Subjects
- Acetylation, Cell Line, Cytoplasm metabolism, Humans, Lysine genetics, Lysine metabolism, Mutation, Peptide Initiation Factors genetics, RNA-Binding Proteins genetics, Eukaryotic Translation Initiation Factor 5A, Lysine analogs & derivatives, Peptide Initiation Factors metabolism, Protein Processing, Post-Translational, RNA-Binding Proteins metabolism
- Abstract
Eukaryotic translation initiation factor 5A (eIF5A) is a highly conserved protein essential for eukaryotic cell proliferation and is the only protein containing hypusine, [N(epsilon)-(4-amino-2-hydroxybutyl)lysine]. eIF5A is activated by the post-translational synthesis of hypusine. eIF5A also undergoes an acetylation at specific Lys residue(s). In this study, we have investigated the effect of hypusine modification and acetylation on the subcellular localization of eIF5A. Immunocytochemical analyses showed differences in the distribution of non-hypusinated eIF5A precursor and the hypusine-containing mature eIF5A. While the precursor is found in both cytoplasm and nucleus, the hypusinated eIF5A is primarily localized in cytoplasm. eIF5A mutant proteins, defective in hypusine modification (K50A, K50R) were localized in a similar manner to the eIF5A precursor, whereas hypusine-modified mutant proteins (K47A, K47R, K68A) were localized mainly in the cytoplasm. These findings provide strong evidence that the hypusine modification of eIF5A dictates its localization in the cytoplasmic compartment where it is required for protein synthesis.
- Published
- 2009
- Full Text
- View/download PDF
49. Reduction of genotoxic effects of N-nitrosomorpholine in human hepatoma cells and hamster lung cells by carboxymethyl chitin-glucan.
- Author
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Slamenova D, Sramkova M, Chalupa I, Smigova J, and Kogan G
- Subjects
- Animals, Cell Line, Chitin pharmacology, Cricetinae, DNA Damage, Humans, Lung, Mutagens toxicity, Tumor Cells, Cultured, Antimutagenic Agents pharmacology, Carcinoma, Hepatocellular genetics, Chitin analogs & derivatives, Chromosome Aberrations, Glucans pharmacology, Liver Neoplasms genetics, Nitrosamines toxicity
- Abstract
N-nitrosomorpholine (NMOR) belongs to the group of N-nitrosamines and represents a known hepatocarcinogen. Exposure to this compound is considered to be a potential health hazard to humans. There is, however, considerable evidence that the effect of many carcinogenic agents can be markedly influenced or altered by various natural substances. The objective of this study was to assess the DNA-protective and anticlastogenic effects of the derivative of a natural compound, carboxymethyl chitin-glucan (CM-CG), against genotoxicity of N-nitrosomorpholine (NMOR) in human hepatoma cells HepG2 and hamster lung cells V79 cultured in vitro. The exponentially growing cells were pre-treated during 24 h with three different concentrations of CM-CG (150, 750 and 1500 mg/ml) and then treated with different concentrations of NMOR. DNAprotective effects of CM-CG were evaluated by single-cell gel electrophoresis (SCGE, comet assay) and anticlastogenic effects by chromosomal aberration assay. At the SCGE assay a short-term (30 min) and at the chromosomal aberration assay a continuous treatment with NMOR was used. In both HepG2 and V79 cells pre-treated with CM-CG, a significant decrease of the percentage of DNA lesions induced by NMOR was observed along with a reduction of NMOR-induced chromosomal aberrations. We did not find any substantial differences between the genotoxic effects of NMOR on HepG2 and V79 cells, which have different histopathological origins and different levels of metabolizing enzymes. Three different concentrations of CM-CG exerted a similar protective effect against NMOR-induced DNA lesions and chromosomal aberrations in both HepG2 and V79 cells.
- Published
- 2008
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