Zebrafish

In this ecotoxicological study, the biological effects of a major class of environmental pollutants are studied using a systems biology approach, assessing these effects across different levels of bio

Peroxisome proliferator activated receptor (PPARs) are members of the of the nuclear hormone receptor superfamily and are implicated in a variety of fundamental biological processes such as lipid metablism, inflammation and cell differentiation. PPARs are ligand mediated transcription factors that can be activated by a group of structurally diverse man-made chemicals, the so called peroxisome prolferators (PPs). This class of PPAR ligands consists of - apart from natural and synthetic fatty acids - a vast amount of human pharmaceuticals (e.g. fibrates) and perfluoralkyl compounds (e.g. PFOS and PFOA), a “new” class of environmental pollutents of which only recently the importance and worldwide dispersion has been reported.

During recent years ecotoxicology has been an emerging field and its experimental focus has been expanded from using mainly chemical stressors (e.g. cadmium) to assessing the effects of natural or non-chemical stressors (e.g.

We all know that since the beginning of the 20th century, the industry is the driving force behind the introduction of new chemicals.

Until recently, most studies on endocrine disruption have focused on effects at the physiological level. In this research, we will evaluate the effects of endocrine disruption on a lower (gene expression) and a higher (reproductive behaviour) level of biological organization. Adult zebrafish are exposed to (potential) endocrine disruptors under flow-through conditions. After 4 and 28 days, fish are dissected and gonads are collected for the production of oligonucleotide microarrays. Gonadosomatic index (GSI) and vitellogenin of whole body homogenates are determined after 28 days. During every day of the first and the last week of exposure, fecundity and fertility are evaluated. Hatching is followed up until 4 days post-hatch. On day 4, 14 and 28, reproductive behaviour of 10 zebrafish (5 males and 5 females) in the control and high dose group is recorded at 3 time points, using a 3D-behaviour analysis system. Swimming velocity, swimming height and inter-individual interactions are calculated.