The cell transformation assay to assess potential carcinogenic properties of nanoparticles.

Nanoparticles (NPs) are present in many daily life products with particular physical-chemical properties (size, density, porosity, geometry …) giving very interesting technological properties. Their use is continuously growing and NPs represent a new challenge in terms of risk assessment, consumers being multi-exposed. Toxic effects have already been identified such as oxidative stress, genotoxicity, inflammatory effects, and immune reactions, some of which are leading to carcinogenesis. Cancer is a complex phenomenon implying multiple modes of action and key events, and prevention strategies in cancer include a proper assessment of the properties of NPs. Therefore, introduction of new agents like NPs into the market creates fresh regulatory challenges for an adequate safety evaluation and requires new tools. The Cell Transformation Assay (CTA) is an in vitro test able of highlighting key events of characteristic phases in the cancer process, initiation and promotion. This review presents the development of this test and its use with NPs. The article underlines also the critical issues to address for assessing NPs carcinogenic properties and approaches for improving its relevance.

Comparison of cell viability between mouse-derived ES-D3 cells and Balb/c 3T3 cells using denture-base lining materials.

The study was done to compare cell viability between ES-D3 and Balb/c 3T3 cells, and evaluate the difference in cell viability between these cell lines using denture-base lining materials for prosthetic dentistry. To compare the cytotoxicity, three acrylic and three silicone dental materials were used. The cell viability was examined by MTT and lactate dehydrogenase (LDH) methods. The cell viability immediately after malaxation or light irradiation was lower only for the acrylic materials in 3T3 cells, and for both silicone and acrylic materials in ES-D3 cells. However, the cell viability determined 24 h after malaxation or light irradiation by the MTT and LDH methods did not significantly differ between samples. It was observed that ES-D3 cells are more sensitive depending on the type of material. The results suggest that ES-D3 cells can be used as in vitro systems for conducting biosafety assessment to predict embryotoxicity.

Determination of the Phototoxicity Potential of Commercially Available Tattoo Inks Using the 3T3-neutral Red Uptake Phototoxicity Test

Objectives: Tattooing is an ancient practice and its popularity has been increasing in the recent years. After tattooing, complications may occur related to compose tattoo inks. In this study, the phototoxicity potential of the blue, red and black colors of the most commonly used three different commercially-available tattoo ink brands have been examined by performing in vitro 3T3-neutral red uptake (NRU) phototoxicity test. Materials and Methods: In the study, the phototoxicity of serial diluted concentrations of tattoo inks were evaluated with in vitro 3T3-NRU phototoxicity test method according to OECD guide 432. The data obtained from the NRU test result were uploaded to Phototox software (version 2.0) and the phototoxicity potentials of tattoo inks were determined via the calculation of the mean photo effect (MPE) and photo irritation factor (PIF) values. Results: The red, black and blue colors of three different commercially available tattoo inks did not cause a cytotoxic activity on BALB/c 3T3 cells with 3T3-NRU test. The IC50 values could not be determined +ultraviolet (UV) and -UV conditions. PIF values could not be calculated and MPE values were <0.1, which predicts the absence of phototoxic effect for all of the tested tattoo inks. Conclusion: All tested inks were evaluated as non-phototoxic according to the results of MPE values calculated using Phototox software. However, test results should be verified by other phototoxicity test methods to obtain a comprehensive evaluation of phototoxic complications of different tattoo inks.

Multifunctional Silver(I) Complexes with Metronidazole Drug Reveal Antimicrobial Properties and Antitumor Activity against Human Hepatoma and Colorectal Adenocarcinoma Cells.

Silver salts and azole derivatives are well known for their antimicrobial properties. Recent evidence has demonstrated also their cytotoxic and genotoxic potential toward both normal and cancer cells. Still, little is known about the action of complexes of azoles with silver(I) salts. Thus, the goal of the study was to compare the chemical, cytotoxic and antimicrobial properties of metronidazole complexes with silver(I) nitrate and silver(I) sulfate to metronidazole and pure silver(I) salts. We synthetized a novel complex, [Ag(MTZ)2]2SO4, and confirmed its chemical structure and properties using 1H and 13C NMR spectroscopy and X-Ray, IR and elemental analysis. To establish the stability of complexes [Ag(MTZ)2NO3] and [Ag(MTZ)2]2SO4, they were exposed to daylight and UV-A rays and were visually assessed. Their cytotoxicity toward human cancer cells (HepG2, Caco-2) and mice normal fibroblasts (Balb/c 3T3 clone A31) was determined by MTT, NRU, TPC and LDH assays. The micro-dilution broth method was used to evaluate their antimicrobial properties against Gram-positive and Gram-negative bacteria. A biofilm eradication study was also performed using the crystal violet method and confocal laser scanning microscopy. The photo-stability of the complexes was higher than silver(I) salts. In human cancer cells, [Ag(MTZ)2]2SO4 was more cytotoxic than Ag2SO4 and, in turn, AgNO3 was more cytotoxic than [Ag(MTZ)2NO3]. For Balb/c 3T3 cells, Ag2SO4 was more cytotoxic than [Ag(MTZ)2]2SO4, while the cytotoxicity of AgNO3 and [Ag(MTZ)2NO3] was similar. Metronidazole in the tested concentration range was non-cytotoxic for both normal and cancer cells. The complexes showed increased bioactivity against aerobic and facultative anaerobic bacteria when compared to metronidazole. For the majority of the tested bacterial strains, the silver(I) salts and complexes showed a higher antibacterial activity than MTZ; however, some bacterial strains presented the reverse effect. Our results showed that silver(I) complexes present higher photo-stability, cytotoxicity and antimicrobial activity in comparison to MTZ and, to a certain extent, to silver(I) salts.

[Study on molecular target of Taohong Siwu Decoction in delaying growth of fibroblasts based on network pharmacology].

As a prescription for promoting blood circulation and removing blood stasis, Taohong Siwu Decoction(THSWD) has certain effects in delaying the progression of renal fibrosis. However, as a traditional Chinese medicine compound containing many monomer components, it has been a research hotspot in the field of exploring the research methods and targets for the complex pathological process. The method of activating blood circulation and removing blood stasis has certain clinical effect in retarding the process of IgA nephropathy(IgAN) fibrosis, but the mechanism of action is still unclear. In this study, the network pharmacology method was used to investigate the active ingredients, targets and molecular mechanisms of THSWD in the intervention of IgAN fibrosis. On this basis, in vitro experiments were conducted to verify the effect of THSWD on the expression of ERK factor in BALB/c 3 T3 cells. The active ingredients and targets in THSWD were collected through the TCMSP. Sixty-one active ingredients and 240 targets including luteolin and quercetin were screened, and 185 targets were obtained by intersecting with CTD database to search IgAN related targets. Cytoscape software and STRING database were used to construct "THSWD-active ingredients-targets" network and protein-protein interaction network, and 69 core targets were screened. In DAVID's GO enrichment analysis and KEGG pathway analysis of the core targets and cell experiments, the results showed that ERK was an important factor for THSWD to interfere with IgAN fibrosis, and THSWD intervention could significantly decrease cell activity, ERK1/2 mRNA expression, and p-ERK1/2 protein expression. This study preliminarily revealed that THSWD may delay the growth of fibroblasts by affecting ERK factor and its phosphorylation level.