In Vivo and In Vitro Toxicity Testing of Cyanobacterial Toxins: A Mini-Review

2021 ◽  
pp. 109-150
Author(s):  
Samaneh J. Porzani ◽  
Stella T. Lima ◽  
James S. Metcalf ◽  
Bahareh Nowruzi
1998 ◽  
Vol 26 (1_suppl) ◽  
pp. 93-129 ◽  
Author(s):  
Cecilia Clemedson ◽  
Frank A. Barile ◽  
Barbro Ekwall ◽  
Maria José Gómez-Lechón ◽  
Tony Hall ◽  
...  

Results from tests on the first 30 MEIC reference chemicals in 16 different systems are presented as a prerequisite to the subsequent in vitro/in vivo comparisons of acute toxicity data, i.e. the final MEIC evaluation of all test results of the study. The study is a supplement to the previously published results from 68 methods (including methods 45B and 46B [old numbers]) used to test the same set of chemicals. The strategies and methods of the preceding paper were employed to enable a comparative cytotoxicity analysis of the results from these 68 methods and from the 16 new methods to be made. Principal components analysis (PCA) of 82 assays demonstrated a dominating first component which described as much as 83% of the variance in the toxicity data. This remarkable similarity of all toxicity data was the main finding of the present study, and confirmed the results of the previous study with a less-extensive database. Also, the influence on the general variability of results of several key methodological factors was evaluated by analysis of selected sets of data, including linear regression of the results of pairs of methods, which were similar in all respects except for the factor under analysis. This analysis of the same 82 assays as before also confirmed previous results from the 68 assay database: a) the toxicities of a third of the chemicals increased considerably with exposure time; b) in general, cytotoxicity for human cells was well predicted by cytotoxicity tests with animal cells; c) this prediction was poor for two chemicals, i.e. digoxin and malathion; d) prediction of human cytotoxicity by ecotoxicological tests was only fairly good; e) 25 comparisons of similar assays employing different cell lines showed strikingly similar toxicities (mean R2 = 0.86); f) 22 comparisons of similar pairs of assays employing different primary cultures and cell lines also revealed similar toxicities (mean R2 = 0.79); and g) 15 comparisons of similar assays with different growth/viability endpoint measurements demonstrated strikingly similar toxicities (mean R2 = 0.89). Results b, e, f and g must be the main causes of the general similarity of results, while results a, c and d, together with other factors, could explain the 20% dissimilarity. These findings support the basal cytotoxicity concept and may assist in guiding and refining in vitro toxicity testing in the future.


Author(s):  
M A Akanji

Mitochondria and lysosome have been used to study drug-cell interactions both in vitro and in vivo. However, their preparations to free them from other sub-cellular organelles are tedious and cumbersome. Erythrocytes (being a simple type of cells without sub-cellular organelles and very easy to obtain in pure form) was assessed for in-vitro toxicity testing of selected chemical compounds by monitoring the release of its hemoglobin content as an index of damage to cell membrane. Washed erythrocytes from male wistar rats were prepared in sodium phosphate buffer (pH 7.5) incubated with and without acetylsalicylic acid (a membrane stabilizer) and chloroquine (a membrane labilizer). The light scattering properties of the suspensions and the hemoglobin released were determined using standard methods. Acetylsalicylic acid did not significantly alter the degree of hemolysis (P > 0.05) whereas the chloroquine alone as well as the mixture of acetylsalicylic acid and chloroquine significantly increased (P < 0.05) it. Acetylsalicylic acid stabilized the erythrocytes membrane while chloroquine destroys it causing lysis of the cell membrane. Results obtained in this study suggest that the drugs have interacted with the erythrocytes in a manner that corresponds to their mode of action. Erythrocytes can therefore be used to study interactions between drug molecules and cell membrane.


1990 ◽  
Vol 18 (1_part_1) ◽  
pp. 11-18 ◽  
Author(s):  
Oliver P. Flint

The fullest potential for in vitro evaluation of toxicity will be realised in the context of the process of assessing the risk of human toxicity. This article is an attempt to clarify what contributions can be made by in vitro tests and what types of in vitro test can best be used. In vitro tests are clarified according to the type of biological endpoint evaluated, first into tests for general (‘basal’) cytotoxicity and, secondly, into tests for differentiated cell function. The role of each type of test is analysed and it is suggested that tests for general cytotoxicity, as opposed to differentiated function, are difficult to interpret in terms of in vivo toxicity. A general approach to evaluating in vitro tests is described, and a strategy for using these tests is proposed.


2008 ◽  
Vol 52 (7) ◽  
pp. 2442-2448 ◽  
Author(s):  
Xing-Cong Li ◽  
Melissa R. Jacob ◽  
Shabana I. Khan ◽  
M. Khalid Ashfaq ◽  
K. Suresh Babu ◽  
...  

ABSTRACT Our continuing effort in antifungal natural product discovery has led to the identification of five 6-acetylenic acids with chain lengths from C16 to C20: 6-hexadecynoic acid (compound 1), 6-heptadecynoic acid (compound 2), 6-octadecynoic acid (compound 3), 6-nonadecynoic acid (compound 4), and 6-icosynoic acid (compound 5) from the plant Sommera sabiceoides. Compounds 2 and 5 represent newly isolated fatty acids. The five acetylenic acids were evaluated for their in vitro antifungal activities against Candida albicans, Candida glabrata, Candida krusei, Candida tropicalis, Candida parapsilosis, Cryptococcus neoformans, Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Trichophyton mentagrophytes, and Trichophyton rubrum by comparison with the positive control drugs amphotericin B, fluconazole, ketoconazole, caspofungin, terbinafine, and undecylenic acid. The compounds showed various degrees of antifungal activity against the 21 tested strains. Compound 4 was the most active, in particular against the dermatophytes T. mentagrophytes and T. rubrum and the opportunistic pathogens C. albicans and A. fumigatus, with MICs comparable to several control drugs. Inclusion of two commercially available acetylenic acids, 9-octadecynoic acid (compound 6) and 5,8,11,14-eicosatetraynoic acid (compound 7), in the in vitro antifungal testing further demonstrated that the antifungal activities of the acetylenic acids were associated with their chain lengths and positional triple bonds. In vitro toxicity testing against mammalian cell lines indicated that compounds 1 to 5 were not toxic at concentrations up to 32 μM. Furthermore, compounds 3 and 4 did not produce obvious toxic effects in mice at a dose of 34 μmol/kg of body weight when administered intraperitoneally. Taking into account the low in vitro and in vivo toxicities and significant antifungal potencies, these 6-acetylenic acids may be excellent leads for further preclinical studies.


1996 ◽  
Vol 24 (1_part_1) ◽  
pp. 273-311 ◽  
Author(s):  
Cecilia Clemedson ◽  
Elisabeth McFarlane-Abdulla ◽  
Marianne Andersson ◽  
Frank A. Barile ◽  
Mabel C. Calleja ◽  
...  

Results from tests of the first 30 MEIC reference chemicals in 68 different toxicity assays are presented as a prerequisite to subsequent in vitro/in vivo comparisons of acute toxicity data. A comparative cytotoxicity study was also carried out. Firstly, the variability of all of the results was analysed by using principal components analysis (PCA), analyses of variance (ANOVAs) and pairwise comparisons of means according to Tukey's method. The first PCA component described 80% of the variance of all of the cytotoxicity data. Tukey's ANOVA indicated a similar sensitivity for the assays, of approximately 80%. Secondly, the influence of five major methodological components on the general variability of the results was evaluated by linear regression and ANOVA linear contrast analyses. The findings were that: a) the toxicity of many chemicals increased with exposure time; b) in general, human cytotoxicity was predicted well by animal cytotoxicity tests; c) this prediction was poor for two chemicals; d) the prediction of human cytotoxicity by the ecotoxicological tests was only fairly good; e) one organotypic endpoint used, i.e. contractility of muscle cells, gave different results to those obtained according to viability/growth toxicity criteria; f) twelve comparisons of similar test systems involving different cell types (including highly differentiated cells) showed similar toxicities regardless of cell type; and g) nine out often comparisons of test systems with identical cell types and exposure times revealed similar toxicities, regardless of the viability or growth endpoint measurement used. Factors b, f and g must be the main causes of the remarkable similarity between the total results, while factors a, c, d and e, together with other minor factors that were not analysed, contributed to the 20% dissimilarity. The findings strongly support the basal cytotoxicity concept, and will facilitate future in vitro toxicity testing.


1993 ◽  
Vol 21 (2) ◽  
pp. 191-195 ◽  
Author(s):  
Knut-Jan Andersen ◽  
Erik Ilsø Christensen ◽  
Hogne Vik

The tissue culture of multicellular spheroids from the renal epithelial cell line LLC-PK1 (proximal tubule) is described. This represents a biological system of intermediate complexity between renal tissue in vivo and simple monolayer cultures. The multicellular structures, which show many similarities to kidney tubules in vivo, including a vectorial water transport, should prove useful for studying the potential nephrotoxicity of drugs and chemicals in vitro. In addition, the propagation of renal epithelial cells as multicellular spheroids in serum-free culture may provide information on the release of specific biological parameters, which may be suppressed or masked in serum-supplemented media.


Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1929
Author(s):  
Tereza Cervena ◽  
Andrea Rossnerova ◽  
Tana Zavodna ◽  
Jitka Sikorova ◽  
Kristyna Vrbova ◽  
...  

The evaluation of the frequency of micronuclei (MN) is a broadly utilised approach in in vitro toxicity testing. Nevertheless, the specific properties of nanomaterials (NMs) give rise to concerns regarding the optimal methodological variants of the MN assay. In bronchial epithelial cells (BEAS-2B), we tested the genotoxicity of five types of NMs (TiO2: NM101, NM103; SiO2: NM200; Ag: NM300K, NM302) using four variants of MN protocols, differing in the time of exposure and the application of cytochalasin-B combined with the simultaneous and delayed co-treatment with NMs. Using transmission electron microscopy, we evaluated the impact of cytochalasin-B on the transport of NMs into the cells. To assess the behaviour of NMs in a culture media for individual testing conditions, we used dynamic light scattering measurement. The presence of NMs in the cells, their intracellular aggregation and dispersion properties were comparable when tests with or without cytochalasin-B were performed. The genotoxic potential of various TiO2 and Ag particles differed (NM101 < NM103 and NM302 < NM300K, respectively). The application of cytochalasin-B tended to increase the percentage of aberrant cells. In conclusion, the comparison of the testing strategies revealed that the level of DNA damage induced by NMs is affected by the selected methodological approach. This fact should be considered in the interpretation of the results of genotoxicity tests.


2021 ◽  
Vol 5 ◽  
pp. 239784732110222
Author(s):  
David Thorne ◽  
Roman Wieczorek ◽  
Toshiro Fukushima ◽  
Han-Jae Shin ◽  
Robert Leverette ◽  
...  

During a Cooperation Centre for Scientific Research Relative to Tobacco (CORESTA) meeting, the in vitro toxicity testing Sub-Group (IVT SG) met to discuss the evolving field of aerosol exposure research. Given the diversity of exposure parameters and biological endpoints being used, it was considered a high priority to investigate and contextualise the responses obtained. This is particularly driven by the inability to compare between studies on different exposure systems due to user preferences and protocol differences. Twelve global tobacco and contract research companies met to discuss this topic and formulate an aligned approach on how this diverging field of research could be appropriately compared. Something that is becoming increasingly important, especially in the light of more focused regulatory scrutiny. A detailed and comprehensive survey was conducted on over 40 parameters ranging from aerosol generation, dilution and data analysis across eight geographically independent laboratories. The survey results emphasise the diversity of in vitro exposure parameters and methodologies employed across the IVT SG and highlighted pockets of harmonisation. For example, many of the biological protocol parameters are consistent across the Sub-Group. However, variables such as cell type and exposure time remain largely inconsistent. The next steps for this work will be to map parameters and system data against biological findings and investigate whether the observed inconsistencies translate into increased biological variability. The results from the survey provide improved awareness of parameters and nuances, that may be of substantial benefit to scientists in intersecting fields and in the development of harmonised approaches.


Author(s):  
Danlei Wang ◽  
Maartje H. Rietdijk ◽  
Lenny Kamelia ◽  
Peter J. Boogaard ◽  
Ivonne M. C. M. Rietjens

AbstractDevelopmental toxicity testing is an animal-intensive endpoints in toxicity testing and calls for animal-free alternatives. Previous studies showed the applicability of an in vitro–in silico approach for predicting developmental toxicity of a range of compounds, based on data from the mouse embryonic stem cell test (EST) combined with physiologically based kinetic (PBK) modelling facilitated reverse dosimetry. In the current study, the use of this approach for predicting developmental toxicity of polycyclic aromatic hydrocarbons (PAHs) was evaluated, using benzo[a]pyrene (BaP) as a model compound. A rat PBK model of BaP was developed to simulate the kinetics of its main metabolite 3-hydroxybenzo[a]pyrene (3-OHBaP), shown previously to be responsible for the developmental toxicity of BaP. Comparison to in vivo kinetic data showed that the model adequately predicted BaP and 3-OHBaP blood concentrations in the rat. Using this PBK model and reverse dosimetry, a concentration–response curve for 3-OHBaP obtained in the EST was translated into an in vivo dose–response curve for developmental toxicity of BaP in rats upon single or repeated dose exposure. The predicted half maximal effect doses (ED50) amounted to 67 and 45 mg/kg bw being comparable to the ED50 derived from the in vivo dose–response data reported for BaP in the literature, of 29 mg/kg bw. The present study provides a proof of principle of applying this in vitro–in silico approach for evaluating developmental toxicity of BaP and may provide a promising strategy for predicting the developmental toxicity of related PAHs, without the need for extensive animal testing.


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