Utility of the C. Elegans Model as a Multi-flexible Platform for Biological Effects of Nanomaterials
Prof. Chunying Chen’s group and Prof. Zhiyong Tang’s group at National Center for Nanoscience and Technology have published their collaborative research article “Full Assessment of Fate and Physiological Behavior of Quantum Dots Utilizing Caenorhabditis Elegans as a Model Organism” in Nano Letters (2011, 11: 3174-3183).
Understanding of the fate and toxicological behavior of nanomaterials in vivo has becoming hotspot in the study of biological effects of nanomaterials. Due to the novel physicochemical properties of nanomaterials, most traditional techniques give limited information on the interaction of nanoparticles with biological system. Thus, it requires developing a simple but efficient platform suitable for systematic investigation, particularly when nanomaterials are present in an already complex biological environment. The task is challenging as it requires both a radical shift of thinking compared with bulk material study, and more importantly, the development of new methodology for nanotoxicological studies.
Caenorhabditis elegans (C. elegans) has been extensively used to study biological processes but seldom used for studies on nanomaterials. As a simple model organism, C. elegans bridges the gap between in vivo and in vitro approaches, since it not only provides physiologically relevant data at a whole-animal level, but also allows analysis at single cell level. In this work, by adopting C. elegans as a model organism and employing integrated techniques, we systematically investigated Quantum dot (QD) uptake by ingestion in natural feeding environment and long-term toxicity on reproductive system, as well as the fate and degradation of QDs in vivo. QDs were found to be accumulated and degradated in the alimentary system, then transferred to the reproductive system and result in accumulative toxicity to reproduction and development of next generation after chronic exposure.
Synchrotron radiation based techniques provide particular advantages in elemental mapping and structure characterization of nanomaterials. They can supplement the unreliability for traditional QDs quantification method using photoluminescence. They established a state-of-art technical platform by integrating GFP transfection, fluorescent imaging and synchrotron radiation based elemental imaging and speciation techniques, which was the first exploration using both in situ and in vivo imaging for systematical evaluating the fate and physiological behavior of QDs in living organisms.
This work highlights the utility of the C. elegans model as a multi-flexible platform to allow non-invasively imaging and monitoring in vivo consequences of nanomaterials. It is hopeful for a broader usage in the toxicological studies of various kinds of nanomaterials.
Recently, Prof. Chunying Chen’s groups have published a series of collaborative researches about biological effects of nanomaterials. The influence of nanomaterial with different sizes and surface charges on the intracellular dynamics and impacts to the mitosis and cell cycle has been published in Biomaterials (2011, 32: 8291-303). Death receptor mediated apoptosis can be inhibited through lysosome stabilization following internalization of carboxyfullerene nanoparticles (Biomaterials, 2011, 32:4030-4041). A review focused on the fate and toxicity of metallic and metal-containing nanoparticles for biomedical applications has been recently published in Small (2011, 10.1002/smll.201101059). These researches help to add new insights into full understanding of the potential toxicity of nanoparticles, and moreover, provide information on the rational design and safe application of nanomaterials.
The aforementioned researches were financially supported by Chinese Academy of Sciences, National Basic Research Program of China from Ministry of Science and Technology, and National Natural Science Foundation of China.
Figure. Utility of the C. elegans model for in situ and in vivo analysis of fate and physiological behavior of Quantum Dots.