In vitro evaluation of the genotoxicity of CeO2 nanoparticles in human peripheral blood lymphocytes using cytokinesis-block micronucleus test, comet assay, and gamma H2AX

Engineered nanoparticles (ENPs) are used in a wide range of applications because of their unique properties. Cerium dioxide nanoparticles (CeO2 NPs) are one of the important ENPs, and they can cause negative health effects, such as genotoxicity, in humans and other living organisms. The aim of this work was to analyze the genotoxic effects of short-term (3–24 h) CeO2 NPs exposure to cultured human blood lymphocytes. Three genotoxicity systems “cytokinesis-block micronucleus test, comet assay, and gamma H2AX test” were used to show the genotoxic potential of CeO2 NPs (particle size <25 nm, concentrations: 6, 12, and 18 µg/mL). Hydrogen peroxide was selected as the positive-control genotoxic agent. Our results indicate that CeO2 NPs have genotoxic potential on human peripheral blood lymphocytes cells even at 3–24 h exposure under in vitro conditions.

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In vitro assessment of the cytotoxic, DNA damaging, and cytogenetic effects of hydroquinone in human peripheral blood lymphocytes

Archives of Industrial Hygiene and Toxicology ◽

10.1515/aiht-2017-68-3060 ◽

2017 ◽

Vol 68 (4) ◽

pp. 322-335 ◽

Cited By ~ 7

Author(s):

Karlo Jurica ◽

Irena Brčić Karačonji ◽

Vesna Benković ◽

Nevenka Kopjar

Keyword(s):

Comet Assay ◽

Peripheral Blood ◽

Human Peripheral Blood ◽

Metabolic Activation ◽

Peripheral Blood Lymphocytes ◽

Alkaline Comet Assay ◽

Blood Lymphocytes ◽

Human Peripheral Blood Lymphocytes ◽

Cytogenetic Effects

Abstract This study investigated the mechanisms of hydroquinone toxicity and assessed the relationships between its cytotoxic, genotoxic, and cytogenetic effects tested at 8, 140, and 280 μg mL-1 in human peripheral blood lymphocytes exposed for 24 h. The outcomes of the treatments were evaluated using the apoptosis/necrosis assay, the alkaline comet assay, and the cytokinesis-block micronucleus (CBMN) cytome assay. The tested hydroquinone concentrations produced relatively weak cytotoxicity in resting lymphocytes, which mostly died via apoptosis. Hydroquinone’s marked genotoxic effects were detected using the alkaline comet assay. Significantly decreased values of all comet parameters compared to controls indicated specific mechanisms of hydroquinone-DNA interactions. Our results suggest that the two higher hydroquinone concentrations possibly led to cross-linking and adduct formation. Increased levels of DNA breakage measured following exposure to the lowest concentration suggested mechanisms related to oxidative stress and inhibition of topoisomerase II. At 8 μg mL-1, hydroquinone did not significantly affect MN formation. At 140 and 280 μg mL-1, it completely blocked lymphocyte division. The two latter concentrations also led to erythrocyte stabilization and prevented their lysis. At least two facts contribute to this study’s relevance: (I) this is the first study that quantifies the degree of reduction in total comet area measured in lymphocyte DNA after hydroquinone treatment, (II) it is also the first one on a lymphocyte model that adopted the “cytome” protocol in an MN assay and found that lymphocytes exposure even to low hydroquinone concentration resulted in a significant increase of nuclear bud frequency. Considering the limitations of the lymphocyte model, which does not possess intrinsic metabolic activation, in order to unequivocally prove the obtained results further studies using other appropriate cell lines are advised.

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Cytotoxic, clastogenic and genotoxic effects of cis-tetraammine(oxalato)ruthenium(III) dithionate on human peripheral blood lymphocytes

Acta Scientiarum Biological Sciences ◽

10.4025/actascibiolsci.v42i1.50517 ◽

2020 ◽

Vol 42 ◽

pp. e50517

Author(s):

Manuela da Rocha Matos Rezende ◽

Vivianne de Souza Velozo-Sá ◽

Cesar Augusto Sam Tiago Vilanova-Costa ◽

Elisangela Silveira-Lacerda

Keyword(s):

Comet Assay ◽

Peripheral Blood ◽

Human Peripheral Blood ◽

Human Lymphocytes ◽

Low Frequency ◽

Peripheral Blood Lymphocytes ◽

Negative Control ◽

Blood Lymphocytes ◽

Human Peripheral Blood Lymphocytes

There is a concern about stablishing the clinical risk of drugs used for cancer treatment. In this study, the cytotoxic, clastogenic and genotoxic properties of cis-tetraammine(oxalato)ruthenium(III) dithionite - cis-[Ru(C2O4)(NH3)4]2(S2O6), were evaluated in vitro in human lymphocytes. The mitotic index (MI), chromosomal aberrations (CA) and DNA damage by comet assay were also analyzed. The MTT test revealed that the ruthenium compound showed a slight cytotoxic effect at the highest concentration tested. The IC50 value for the compound after 24 hours of exposure was 185.4 µM. The MI values of human peripheral blood lymphocytes treated with 0.015, 0.15, 1.5 and 150 µM of cis-[Ru(C2O4)(NH3)4]2(S2O6) were 6.1, 3.9, 3.2 and 0.2%, respectively. The lowest concentration, 0.015 µM, did not show any cytotoxic activity. The CA values for the 0.015, 0.15 and 1.5 µM concentrations presented low frequency (1.5, 1.6 and 2.3%, respectively), and did not express clastogenic activity when compared to the negative control, although it was observed clastogenic activity in the highest concentration tested (150 µM). The results obtained by the comet assay suggest that this compound does not present genotoxic activity at lower concentrations. The results show that cis-[Ru(C2O4)(NH3)4]2(S2O6) has no cytotoxic, clastogenic or genotoxic in vitro effects at concentrations less than or equal to 0.015 µM. This information proves as promising in the treatment of cancer and is crucial for future trials.

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Genotoxic evaluation of common commercial pesticides in human peripheral blood lymphocytes

Toxicology and Industrial Health ◽

10.1177/0748233717736121 ◽

2017 ◽

Vol 33 (12) ◽

pp. 938-945 ◽

Cited By ~ 4

Author(s):

Cynthia Paz-Trejo ◽

Sandra Gómez-Arroyo

Keyword(s):

Peripheral Blood ◽

Human Peripheral Blood ◽

Peripheral Blood Lymphocytes ◽

Negative Control ◽

Blood Lymphocytes ◽

Human Peripheral Blood Lymphocytes ◽

Genotoxic Potential ◽

Apoptosis And Necrosis

This study aims to evaluate the genotoxic potential of four commercial pesticides with diverse health categorizations by different world associations currently in use. We tested the fungicide mancozeb and the insecticides pirimicarb, monocrotophos and permethrin. The research was done with in vitro human peripheral blood lymphocytes using the DNA single gel electrophoresis assay and the cytokinesis-block micronucleus (MN) test, where we analysed common parameters such as the tail moment and the frequency of MN formation. We also measured other parameters like frequency of nucleoplasmic bridges, nuclear buds, apoptosis and necrosis with the MN test. Each pesticide induced significant differences in all of these parameters when compared with the negative control and showed different behaviours in the concentration-dependent response. This could be attributed to their genotoxic potential where mancozeb and monocrotophos induced the highest genetic damage, permethrin caused mainly cell death and pirimicarb had the least impact upon cells. This research provides valuable data about the harmful effects of these pesticides on human cells and may be an important contribution in the construction of a unique international classification of health and to reinforce the use of genotoxic analyses to regulate the use of pesticides.

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