title: ZnPP reduces autophagy and induces apoptosis, thus aggravating liver ischemia/reperfusion injury in vitro.
abstract: There is growing evidence indicating that autophagy plays a protective role in liver ischemia/reperfusion (IR) injury. Heme oxygenase-1 (HO-1) can also prevent liver IR injury by limiting inflammation and inducing an anti-apoptotic response. Autophagy also plays a crucial role in liver IR injury. The aim of the present study was to investigate the role of HO-1 in liver IR injury and the association between HO-1, autophagy and apoptotic pathways. IR simulation was performed using buffalo rat liver (BRL) cells, and HO-1 activity was either induced by hemin (HIR group) or inhibited by zinc protoporphyrin (ZnPP) (ZIR group). In the HIR and ZIR group, the expression of HO-1 and autophagy-related genes [light chain 3-Ⅱ (LC3-Ⅱ)] was assessed by RT-qPCR and the protein expression of caspases, autophagy-related genes and genes associated with apoptotic pathways (Bax) was detected by western blot anlaysis. The results of RT-PCR revealed the genetically decreased expression of HO-1 and autophagy-related genes in the ZIR group. Similar results were obtained by western blot analysis and immunofluorescence. An ultrastructural analysis revealed a lower number of autophagosomes in the ZIR group; in the HIR group, the number of autophagosomes was increased. The expression of Bax and cytosolic cytochrome c was increased, while that of Bcl-2 was decreased following treatment of the cells with ZnPP prior to IR simulation; the oppostie occurred in the HIR group. Cleaved caspase-3, caspase-9 and poly(ADP-ribose) polymerase (PARP) protein were activated in the IR and ZIR groups. The disruption of mitochondrial membrane potential was also observed in the ZIR group. In general, the downregulation of HO-1 reduced autophagy and activated the mitochondrial apoptotic pathway.
authors.affiliation: Department of Oncological Surgery 2, Xuzhou City Central Hospital, The Affiliated Hospital of Southeast University Medical School (Xuzhou), The Tumor Research Institute of Southeast University (Xuzhou), Xuzhou, Jiangsu 221009, P.R. China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Gastroenterology 2, Xuzhou City Central Hospital, The Affiliated Hospital of Southeast University Medical School (Xuzhou), Xuzhou, Jiangsu 221009, P.R. China.
authors.forename: Xuanxuan
authors.initials: X
authors.lastname: Xiong
authors.affiliation: Department of Oncological Surgery 2, Xuzhou City Central Hospital, The Affiliated Hospital of Southeast University Medical School (Xuzhou), The Tumor Research Institute of Southeast University (Xuzhou), Xuzhou, Jiangsu 221009, P.R. China.
authors.forename: Hao
authors.initials: H
authors.lastname: Guo
authors.affiliation: Department of Gastroenterology 2, Xuzhou City Central Hospital, The Affiliated Hospital of Southeast University Medical School (Xuzhou), Xuzhou, Jiangsu 221009, P.R. China.
authors.forename: Mingbo
authors.initials: M
authors.lastname: Wu
authors.affiliation: Key Laboratory of Living Donor Liver Transplantation, Ministry of Public Health, Liver Transplantation Center, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China.
authors.forename: Xiangcheng
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Oncological Surgery 2, Xuzhou City Central Hospital, The Affiliated Hospital of Southeast University Medical School (Xuzhou), The Tumor Research Institute of Southeast University (Xuzhou), Xuzhou, Jiangsu 221009, P.R. China.
authors.forename: Yuanchao
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Department of Oncological Surgery 2, Xuzhou City Central Hospital, The Affiliated Hospital of Southeast University Medical School (Xuzhou), The Tumor Research Institute of Southeast University (Xuzhou), Xuzhou, Jiangsu 221009, P.R. China.
authors.forename: Guangwei
authors.initials: G
authors.lastname: Xie
authors.affiliation: Department of General Surgery, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210011, P.R. China.
authors.forename: Jian
authors.initials: J
authors.lastname: Shen
authors.affiliation: Department of Oncological Surgery 2, Xuzhou City Central Hospital, The Affiliated Hospital of Southeast University Medical School (Xuzhou), The Tumor Research Institute of Southeast University (Xuzhou), Xuzhou, Jiangsu 221009, P.R. China.
authors.forename: Qingzhong
authors.initials: Q
authors.lastname: Tian
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects* / Q000235:genetics; D001343:Autophagy / Q000187:drug effects* / Q000235:genetics; D015153:Blotting, Western; D020169:Caspases / Q000378:metabolism; D002478:Cells, Cultured; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects; D051547:Heme Oxygenase-1 / Q000235:genetics / Q000378:metabolism; D022781:Hepatocytes / Q000187:drug effects* / Q000378:metabolism; D008099:Liver / Q000098:blood supply / Q000187:drug effects; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D046529:Microscopy, Electron, Transmission; D008856:Microscopy, Fluorescence; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism; D010588:Phagosomes / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D011524:Protoporphyrins / Q000494:pharmacology*; D011915:Rats, Inbred BUF; D015427:Reperfusion Injury; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D020169:Caspases; D004791:Enzyme Inhibitors; D051547:Heme Oxygenase-1; D008869:Microtubule-Associated Proteins; D011065:Poly(ADP-ribose) Polymerases; D019253:Proto-Oncogene Proteins c-bcl-2; D011524:Protoporphyrins; D051028:bcl-2-Associated X Protein; C494828:Bax protein, rat; C526109:Anxa3 protein, rat; C017803:zinc protoporphyrin