1. Exposure of fathead minnows to municipal wastewater effluent affects intracellular signaling pathways in the liver
- Author
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François Gagné, Daniel G. Cyr, Jennifer Arstikaitis, Institut Armand Frappier ( INRS-IAF ), Institut National de la Recherche Scientifique [Québec] ( INRS ) -Réseau International des Instituts Pasteur ( RIIP ) -Institut Armand Frappier, Environment and Climate Change Canada, and This work was supported by grants from NSERC (155065-06), the Canadian Water Network, Fonds de Recherches Santé du Québec-Réseau de recherches en santé environnementale to DGC and from Environment Canada to FG.
- Subjects
Physiology ,Health, Toxicology and Mutagenesis ,[ SDV.TOX ] Life Sciences [q-bio]/Toxicology ,010501 environmental sciences ,Microarray ,Wastewater ,Toxicology ,01 natural sciences ,Biochemistry ,WNT4 ,Oligonucleotide Array Sequence Analysis ,0303 health sciences ,biology ,MESH : Gene Expression Regulation ,Kinase ,Wnt signaling pathway ,Quebec ,LRP6 ,General Medicine ,6. Clean water ,Cell biology ,MESH : Oligonucleotide Array Sequence Analysis ,Liver ,Intracellular signaling ,Toxicity ,Signal transduction ,Signal Transduction ,medicine.medical_specialty ,Cell signaling ,MESH : Water Pollutants, Chemical ,MESH : Quebec ,Cyprinidae ,Fathead minnow ,03 medical and health sciences ,Vitellogenin ,Internal medicine ,MESH : Cyprinidae ,medicine ,Animals ,14. Life underwater ,030304 developmental biology ,0105 earth and related environmental sciences ,MESH : Signal Transduction ,MESH : Liver ,Cell Biology ,Environmental Exposure ,Endocrinology ,Gene Expression Regulation ,biology.protein ,MESH : Animals ,MESH : Waste Water ,MESH : Environmental Exposure ,Water Pollutants, Chemical - Abstract
International audience; Municipal wastewater effluent can impact its receiving environment. In the St. Lawrence River, male fish living downstream from Montreal exhibit increased hepatic vitellogenin, intersex, delayed spermatogenesis and altered immune function. Few studies have examined genome-wide effects associated with municipal effluent exposure in fish to decipher the mechanisms of toxicity. The present objective was to identify hepatic cellular signaling pathways in fathead minnows following exposure to municipal wastewater effluent. Immature minnows were exposed for 21 days to either 0% (Control) or 20% municipal effluent, the highest concentration in the St. Lawrence River. Hepatic RNA was extracted and used to hybridize a fathead minnow oligonucleotide microarray containing approximately 15 k gene sequences. A total of 1300 genes were differentially expressed, of which 309 genes had more than 2-fold change in expression level between control and MWWE-exposed fish. Of those, 118 were up-regulated and 191 were down-regulated. Altered genes grouped according to function, indicated effects on various signaling pathways, apoptosis, immune responses, and cellular metabolism. Pathway analysis software predicted at least 5 signaling pathways that were altered by treatment: cell adhesion, inflammation, various kinases, estrogen receptor signaling and WNT signaling. Various components of the canonical Wnt pathway were dramatically down-regulated, while several other genes involved in the non-canonical Wnt pathway, such as Wnt4, LRP6, and PPP2R5E, which are known to inhibit the canonical Wnt pathway, were increased. These results indicate that municipal wastewater effluent from Montreal can target and inhibit various signaling including those implicated in hepatic Wnt signaling pathway in fathead minnows.
- Published
- 2014