title: Proteomic responses in the gills of fathead minnows (Pimephales promelas, Rafinesque, 1820) after 6 months and 2 years of continuous exposure to environmentally relevant dietary 226Ra.
abstract: OBJECTIVE
  To investigate changes in the gill proteome of fathead minnows continually fed an environmentally relevant dietary dose of (226)Ra for 2 years.
  
  
  METHODS
  The fish were fed a commercial diet containing 10 mBq-10 Bq (226)Ra g(-1). After 6 months and 2 years the gill proteome was analyzed by two-dimensional electrophoresis (2-DE). Protein spots which exhibited a significant change were identified using mass spectrometry.
  
  
  RESULTS
  Six proteins were found to be increased: Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), enolase, protein disulphide isomerase precursor, ATP synthase, glial cell fibrillary protein (GFAP), apolipoprotein A1 (ApoA1). One protein was found to be decreased; malate dehydrogenase. The majority of these changes occurred predominantly at the lowest (226)Ra doses, within 6 months and were maintained for 2 years.
  
  
  CONCLUSIONS
  These proteomic changes suggested an adaptive or protective response to radiation induced reactive oxygen species (ROS). Increased GFAP indicated the induction of oxidative stress. Increased GAPDH and enolase indicated enhanced ROS scavenging from glycolytic metabolites. Increased protein disulphide isomerase precursor indicated an enhanced source of radioprotective thiols. Decreased malate dehydrogenase indicated enhanced ROS scavenging within the mitochondria. Increased ATP synthase indicated enhanced protection of healthy cells and increased ApoA1 indicated enhanced protection of the gill lamellae.
authors.affiliation: Department of Medical Physics and Applied Radiation Sciences, McMaster University , Hamilton, Ontario , Canada.
authors.forename: Richard W
authors.initials: RW
authors.lastname: Smith
authors.forename: Jiaxi
authors.initials: J
authors.lastname: Wang
authors.forename: Carmel E
authors.initials: CE
authors.lastname: Mothersill
authors.forename: Lucy E J
authors.initials: LE
authors.lastname: Lee
authors.forename: Colin B
authors.initials: CB
authors.lastname: Seymour
mesh_terms: D000821:Animal Feed / Q000009:adverse effects; D000818:Animals; D016632:Apolipoprotein A-I / Q000378:metabolism; D003530:Cyprinidae / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D005260:Female; D029941:Fish Proteins / Q000378:metabolism* / Q000528:radiation effects*; D005507:Food Contamination, Radioactive; D005880:Gills / Q000378:metabolism / Q000528:radiation effects; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000378:metabolism; D008291:Malate Dehydrogenase / Q000378:metabolism; D008297:Male; D020543:Proteome / Q000528:radiation effects*; D040901:Proteomics; D011836:Radiation Tolerance; D011853:Radiobiology; D011883:Radium / Q000008:administration & dosage / Q000009:adverse effects*; D017382:Reactive Oxygen Species / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization; D013997:Time Factors
chemical_list: D016632:Apolipoprotein A-I; D029941:Fish Proteins; D020543:Proteome; D017382:Reactive Oxygen Species; D008291:Malate Dehydrogenase; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D011883:Radium
keywords: 226Ra; dietary exposure; fathead minnow; oxidative stress; proteomics