PMID- 29799837 OWN - NLM STAT- MEDLINE DCOM- 20181126 LR - 20201214 IS - 1932-6203 (Electronic) IS - 1932-6203 (Linking) VI - 13 IP - 5 DP - 2018 TI - Elevated Nrf-2 responses are insufficient to mitigate protein carbonylation in hepatospecific PTEN deletion mice. PG - e0198139 LID - 10.1371/journal.pone.0198139 [doi] LID - e0198139 AB - OBJECTIVE: In the liver, a contributing factor in the pathogenesis of non-alcoholic fatty liver disease (NASH) is oxidative stress, which leads to the accumulation of highly reactive electrophilic alpha/beta unsaturated aldehydes. The objective of this study was to determine the impact of NASH on protein carbonylation and antioxidant responses in a murine model. METHODS: Liver-specific phosphatase and tensin homolog (PTEN)-deletion mice (PTENLKO) or control littermates were fed a standard chow diet for 45-55 weeks followed by analysis for liver injury, oxidative stress and inflammation. RESULTS: Histology and Picrosirius red-staining of collagen deposition within the extracellular matrix revealed extensive steatosis and fibrosis in the PTENLKO mice but no steatosis or fibrosis in controls. Increased steatosis and fibrosis corresponded with significant increases in inflammation. PTEN-deficient livers showed significantly increased cell-specific oxidative damage, as detected by 4-hydroxy-2-nonenal (4-HNE) and acrolein staining. Elevated staining correlated with an increase in nuclear DNA repair foci (gammaH2A.X) and cellular proliferation index (Ki67) within zones 1 and 3, indicating oxidative damage was zonally restricted and was associated with increased DNA damage and cell proliferation. Immunoblots showed that total levels of antioxidant response proteins induced by nuclear factor erythroid-2-like-2 (Nrf2), including GSTmu, GSTpi and CBR1/3, but not HO-1, were elevated in PTENLKO as compared to controls, and IHC showed this response also occurred only in zones 1 and 3. Furthermore, an analysis of autophagy markers revealed significant elevation of p62 and LC3II expression. Mass spectrometric (MS) analysis identified significantly more carbonylated proteins in whole cell extracts prepared from PTENLKO mice (966) as compared to controls (809). Pathway analyses of identified proteins did not uncover specific pathways that were preferentially carbonylated in PTENLKO livers but, did reveal specific strongly increased carbonylation of thioredoxin reductase and of glutathione-S-transferases (GST) M6, O1, and O2. CONCLUSIONS: Results show that disruption of PTEN resulted in steatohepatitis, fibrosis and caused hepatic induction of the Nrf2-dependent antioxidant system at least in part due to elevation of p62. This response was both cell-type and zone specific. However, these responses were insufficient to mitigate the accumulation of products of lipid peroxidation. FAU - Petersen, Dennis R AU - Petersen DR AD - Department of Pharmaceutical Sciences, School of Pharmacy, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America. FAU - Saba, Laura M AU - Saba LM AUID- ORCID: 0000-0001-9649-1294 AD - Department of Pharmaceutical Sciences, School of Pharmacy, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America. FAU - Sayin, Volkan I AU - Sayin VI AD - Department of Pathology, New York University School of Medicine, New York, New York, United States of America. AD - Perlmutter Cancer Center, New York University School of Medicine, New York, New York, United States of America. FAU - Papagiannakopoulos, Thales AU - Papagiannakopoulos T AD - Department of Pathology, New York University School of Medicine, New York, New York, United States of America. AD - Perlmutter Cancer Center, New York University School of Medicine, New York, New York, United States of America. FAU - Schmidt, Edward E AU - Schmidt EE AD - Department of Microbiology and Immunology, Montana State University, Bozeman, Montana, United States of America. FAU - Merrill, Gary F AU - Merrill GF AD - Department of Biochemistry and Biophysics, Oregon State University, Corvalis, Oregon, United States of America. FAU - Orlicky, David J AU - Orlicky DJ AUID- ORCID: 0000-0002-0417-1400 AD - Department of Pathology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America. FAU - Shearn, Colin T AU - Shearn CT AUID- ORCID: 0000-0002-9618-9885 AD - Department of Pharmaceutical Sciences, School of Pharmacy, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America. LA - eng GR - UL1 RR025780/RR/NCRR NIH HHS/United States GR - R21 AG055022/AG/NIA NIH HHS/United States GR - P30 CA046934/CA/NCI NIH HHS/United States GR - F32 AA018613/AA/NIAAA NIH HHS/United States GR - R01 CA154986/CA/NCI NIH HHS/United States GR - R37 AA009300/AA/NIAAA NIH HHS/United States GR - R01 CA215784/CA/NCI NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural DEP - 20180525 PL - United States TA - PLoS One JT - PloS one JID - 101285081 RN - 0 (Aldehydes) RN - 0 (Antioxidants) RN - 0 (NF-E2-Related Factor 2) RN - 0 (Nfe2l2 protein, mouse) RN - EC 3.1.3.67 (PTEN Phosphohydrolase) SB - IM MH - Aldehydes/metabolism MH - Animals MH - Antioxidants/metabolism MH - Autophagy/genetics MH - Cell Proliferation/genetics MH - Female MH - *Gene Knockout Techniques MH - Liver/cytology/*metabolism MH - Male MH - Mice MH - Mice, Inbred C57BL MH - NF-E2-Related Factor 2/*metabolism MH - Organ Specificity MH - Oxidative Stress/genetics MH - PTEN Phosphohydrolase/*deficiency/*genetics MH - Protein Carbonylation/*genetics MH - Proteomics PMC - PMC5969769 COIS- The authors have declared no competing interests exists. EDAT- 2018/05/26 06:00 MHDA- 2018/11/27 06:00 PMCR- 2018/05/25 CRDT- 2018/05/26 06:00 PHST- 2018/02/21 00:00 [received] PHST- 2018/05/14 00:00 [accepted] PHST- 2018/05/26 06:00 [entrez] PHST- 2018/05/26 06:00 [pubmed] PHST- 2018/11/27 06:00 [medline] PHST- 2018/05/25 00:00 [pmc-release] AID - PONE-D-18-05719 [pii] AID - 10.1371/journal.pone.0198139 [doi] PST - epublish SO - PLoS One. 2018 May 25;13(5):e0198139. doi: 10.1371/journal.pone.0198139. eCollection 2018.