title: Proteomic identification of proteins differentially expressed by melatonin in hepatic ischemia-reperfusion injury.
abstract: Hepatic ischemia-reperfusion (I-R) injury induces hepatic dysfunction or failure. Melatonin is a potent free radical scavenger and a strong antioxidant. Although many studies have demonstrated the protective effect of melatonin in hepatic injury, the molecular mechanisms of this protection are unclear. We identified specific proteins that are differentially expressed by melatonin treatment in hepatic I-R injury. Adult mice were subjected to 1 hr of ischemia and 3 hr of reperfusion. Animals were treated with vehicle or melatonin (10 mg/kg, i.p.) 15 min prior to ischemia and just before reperfusion. Serum aspartate aminotransferase and alanine aminotransferase levels were higher in I-R group than in sham-operated group, and these increases were reduced by melatonin treatment. Proteins that were differentially expressed following melatonin treatment during hepatic I-R injury were detected using two-dimensional gel electrophoresis. Hepatic I-R injury induced down-regulation of glyoxalase I, glutaredoxin-3, spermidine synthase, proteasome subunit beta type-4, and dynamin like protein-1 (DLP-1). However, melatonin prevented the reductions in these proteins induced by I-R injury. Among the identified proteins, we focused on DLP-1, which is essential for the maintenance of mitochondrial and endoplasmic reticulum morphology. Western blot analysis confirmed that melatonin prevents the hepatic I-R injury-induced decrease in DLP-1. These results suggest that melatonin protects hepatic cells against hepatic I-R injury and that its protective effects involve the regulation of specific proteins.
authors.affiliation: Department of Anatomy, College of Veterinary Medicine and Research Instituite of Life Science, Gyeongsang National University, Jinju, South Korea.
authors.forename: Eun-Hae
authors.initials: EH
authors.lastname: Cho
authors.forename: Phil-Ok
authors.initials: PO
authors.lastname: Koh
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D000704:Analysis of Variance; D000818:Animals; D001219:Aspartate Aminotransferases / Q000097:blood; D015153:Blotting, Western; D015180:Electrophoresis, Gel, Two-Dimensional; D020558:GTP Phosphohydrolases / Q000378:metabolism; D006651:Histocytochemistry; D020287:In Situ Nick-End Labeling; D008099:Liver / Q000098:blood supply* / Q000187:drug effects*; D008297:Male; D008550:Melatonin / Q000494:pharmacology*; D051379:Mice; D008813:Mice, Inbred ICR; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D020543:Proteome / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism; D040901:Proteomics; D015427:Reperfusion Injury / Q000188:drug therapy / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D008869:Microtubule-Associated Proteins; D020543:Proteome; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; D020558:GTP Phosphohydrolases; D008550:Melatonin