C₆₀ exposure induced tissue damage and gene expression alterations in the earthworm Lumbricus rubellus

Abstract

Effects of C₆₀ exposure (0, 15 or 154 mg/kg soil) on the earthworm Lumbricus rubellus were assessed at the tissue and molecular level, in two experiments. In the first experiment, earthworms were exposed for four weeks, and in the second lifelong. In both experiments, gene expression of heat shock protein 70 (HSP70) decreased. For catalase and glutathione-S-transferase (GST), no significant trends in gene expression or enzyme activity were observed. Gene expression of coelomic cytolytic factor-1 (CCF-1) did not alter in earthworms exposed for four weeks, but was significantly down-regulated in the lifelong exposure. Histology of earthworms exposed to C₆₀ in both experiments showed a damaged cuticle, with underlying pathologies of epidermis and muscles, as well as effects on the gut barrier. However, tissue repair was also observed in these earthworms. Overall, these data show that sub-lethal C₆₀ exposure to earthworms via the soil affects gene expression and causes tissue pathologies.

Keywords::

• Nanoparticles
• soil organisms
• histology
• gene expression
• enzyme activity

Acknowledgements

The authors would like to thank Prof. Dr. ir. Ivonne M.C.M. Rietjens of the Division of Toxicology of the Wageningen University for her valuable scientific input in this study. Laura de Haan, also from the Division of Toxicology of the Wageningen University, is kindly acknowledged for her technical support. We would like to thank Yuya Hayashi (Interdisciplinary Nanoscience Centre (iNANO) and National Environmental Research Institute (NERI) Aarhus University) for his help with the gene expression measurements and Michael Hockings (School of Biomedical and Biological Sciences, University of Plymouth) is thanked for histological technical support. Ivo Laros, from Alterra Wageningen UR, is acknowledged for the useful discussions about enzyme expression and activity. This research project was supported by Wageningen UR strategic research program BioNanotechnology 2007–2011 and research school WIMEK.