M1895 Proteomic Analysis of Hepatic Ischemia/Reperfusion Injury and Ischemic Preconditioning in Mice Revealed the Protective Role of Atp5b
ABSTRACT Hepatic ischemia/reperfusion (I/R) injury is an inevitable consequence during liver surgery. Ischemic preconditioning (IPC) has been shown to protect the livers from I/R injury, partially mediated by preservation of hepatic ATP contents. However, the precise molecular mechanisms of these events remain poorly elucidated. In this study, liver proteomes of the mice subjected to I/R injury pretreated with or without IPC were analyzed using 2-DE combined with MALDI-TOF/TOF mass analysis. Twenty proteins showing more than 1.5-fold difference were identified in the livers upon I/R injury. Among these proteins, four proteins were further regulated by IPC when compared with nonpretreated controls. One of these proteins, ATP synthase β subunit (ATP5β) catalyzes the rate-limiting step of ATP formation. The expression level of ATP5β, which was further validated by Western blot analysis, was significantly decreased upon I/R injury while turned over by IPC pretreatment. Change pattern of hepatic ATP corresponded with that of ATP5β expression, indicating that increasing hepatic ATP5β expression might be a reason for ATP-preserving effect of IPC. In summary, this study provided new clues for understanding the mechanisms of IPC against I/R injury. The protective role of ATP5β might give evidences for developing new therapeutic approaches against hepatic I/R injury.
- SourceAvailable from: Sabarinathan Ramachandran
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- "Proteomics provides one approach to identify and study potential biomarkers and mediators and offers the advantage of elucidating overall patterns of injury-induced changes at the protein level, including both changes in relative protein abundance and post-translational modifications of proteins [8,9]. Proteomics has been successfully employed in the study of various liver injury models and models of ischemia/reperfusion (I/R) [10-15]. High levels of oxidative stress and decreased levels of antioxidant proteins have been implicated as important mediators of injury due to ethanol-induced steatosis . "
ABSTRACT: The molecular basis of the increased susceptibility of steatotic livers to warm ischemia/reperfusion (I/R) injury during transplantation remains undefined. Animal model for warm I/R injury was induced in obese Zucker rats. Lean Zucker rats provided controls. Two dimensional differential gel electrophoresis was performed with liver protein extracts. Protein features with significant abundance ratios (p < 0.01) between the two cohorts were selected and analyzed with HPLC/MS. Proteins were identified by Uniprot database. Interactive protein networks were generated using Ingenuity Pathway Analysis and GRANITE software. The relative abundance of 105 proteins was observed in warm I/R injury. Functional grouping revealed four categories of importance: molecular chaperones/endoplasmic reticulum (ER) stress, oxidative stress, metabolism, and cell structure. Hypoxia up-regulated 1, calcium binding protein 1, calreticulin, heat shock protein (HSP) 60, HSP-90, and protein disulfide isomerase 3 were chaperonins significantly (p < 0.01) down-regulated and only one chaperonin, HSP-1was significantly upregulated in steatotic liver following I/R. Down-regulation of the chaperones identified in this analysis may contribute to the increased ER stress and, consequently, apoptosis and necrosis. This study provides an initial platform for future investigation of the role of chaperones and therapeutic targets for increasing the viability of steatotic liver allografts.BMC Biochemistry 09/2012; 13(1):17. DOI:10.1186/1471-2091-13-17 · 1.44 Impact Factor
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ABSTRACT: MicroRNAs are a group of small non-coding RNAs with modulator activity of gene expression. Recent studies have uncovered a profound role of microRNAs in liver diseases. This study aimed to investigate a potential relationship between microRNA-223 (miR-223) expression and hepatic ischemia/reperfusion injury in mice. Quantitative RT-PCR analysis showed that miR-223 expression levels were greatly up-regulated in the livers after 75 min ischemia followed by 120 min reperfusion when compared to sham controls (2.59 +/- 0.23 vs. 0.83 +/- 0.15; P < 0.01). Correlation analysis also revealed that hepatic miR-223 expression level was significantly positively correlated with serum markers of ischemic injury. By prediction assay of miRNA targets mRNA, acyl-CoA synthetase long-chain family member 3, ephrin A1, and ras homolog gene family member B were predicted to be downstream targets of miR-223. Thus, we conclude that hepatic ischemia/reperfusion injury might be another form of liver disease that is associated with alteration in miR-223 expression.Digestive Diseases and Sciences 12/2008; 54(11):2362-6. DOI:10.1007/s10620-008-0629-8 · 2.61 Impact Factor