Evaluation of toxicological and teratogenic effects of carbosilane glucose glycodendrimers in zebrafish embryos and model rodent cell lines

Abstract

Glycodendrimers (Glyco-DDMs) represent a rapidly growing class of nanoparticles with promising properties for biomedical applications but concerns regarding the impact on human health and environment are still justified. Here we report, for the first time, the comparative study of in vivo developmental toxicity of carbosilane Glyco-DDMs and their cytotoxicity in vitro. Carbosilane Glyco-DDMs (generation 1–3) containing 4, 8, and 16 β-d-glucopyranosyl units at the periphery (DDM₁Glu, DDM₂Glu, and DDM₃Glu) were synthesized and characterized by ¹H, ¹³C and ²⁹Si NMR, mass spectrometry, dynamic light scattering, atomic force microscopy (AFM), and computer modeling. In vitro cytotoxicity assay (MTT) of DDM_1–3Glu was performed on three different rodent cell lines (Cricetulus griseus) – B14 (ATCC, CCL-14.1), BRL 3A (ATCC, CRL-1442), and NRK 52E (ATCC, CRL-1571). Overall, very low cytotoxicity was observed with calculated IC₅₀ in mM range with slight difference between each cell line and DDM generation investigated. Modified fish embryo test (FET) was further used for DDM₃Glu developmental toxicity testing on zebrafish (Danio rerio) embryos. While seemingly harmless to intact embryos, adverse effects of DDMs on the embryonic development become evident after chorion removal (LD₅₀=2.78 µM at 96 hpe). We summarized that the modified FET test showed a two to three orders of magnitude difference between the in vitro cytotoxicity and in vivo developmental toxicity of DDM₃Glu. While, in general, the Glyco-DDMs show great promises as efficient vectors in targeted drug delivery or as therapeutic molecules itself, we suggest that their developmental toxicity should be thoroughly investigated to exclude safety risks associated with their potential biomedical use.

Keywords:

• Carbosilane dendrimers
• glycodendrimers
• zebrafish
• toxicity
• teratogenicity
• molecular modeling

Acknowledgments

The authors acknowledge the project No. 15-05903S of the Czech Science Foundation, Internal Grant Agency of UJEP and the assistance provided by the Research Infrastructure NanoEnviCz and the project Pro-NanoEnviCz.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Ministry of Education, Youth and Sports of the Czech Republic and the European Union – European Structural and Investments Funds in the frame of Operational Programme research Development and Education [Project No. LM 2015073 – Research Infrastructure NanoEnviCZ and project No. CZ.02.1.01/0.0/16_013/0001821 – Pro-NanoEnviCZ], Czech Science Foundation [project No. 15-05903S] and Internal Grant Agency of UJEP [project No. UJEP-SGS-2017-53-002-3].