title: Improved islet yields from pancreas preserved in perflurocarbon is via inhibition of apoptosis mediated by mitochondrial pathway.
abstract: Islet transplantation is a treatment option for type I diabetic patients. Preservation of human pancreata prior to islet isolation using two-layer method with perfluorocarbon (PFC) and University of Wisconsin solution (UW) results in twofold increase in islet yields. The objective of this study was to determine the mechanism by which islets undergo apoptosis and determine PFC's effects on this process. Gene array analysis was used to analyze the expression of pro- and anti-apoptotic genes in islets isolated from pancreata preserved under varying conditions. A 12-fold increase in the expression of inhibitor of apoptosis (IAP) and survivin was observed in islets isolated from pancreata preserved in PFC. This was accompanied by decreased expression of BAD (3.7-fold), BAX (2.7-fold) and caspases (5.2-fold). Levels of activated caspase-9 (77.98%), caspase-2 (61.5%), caspase-3 (68.3%) and caspase-8 (37.2%) were also reduced. 'Rescue' of pancreata after storage (12 h) in UW by preservation using PFC also resulted in a down-regulation of pro-apoptotic genes and inhibition of caspase activation. Apoptosis observed in islets from all groups was mainly mitochondria-dependent, mediated by change in redox potential initiated by hypoxia. We demonstrate that reduction in hypoxia of pancreata preserved using PFC leads to significant up-regulation of anti-apoptotic and inhibition of pro-apoptotic genes.
authors.affiliation: Department of Surgery, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: S
authors.initials: S
authors.lastname: Ramachandran
authors.forename: N M
authors.initials: NM
authors.lastname: Desai
authors.forename: T A
authors.initials: TA
authors.lastname: Goers
authors.forename: N
authors.initials: N
authors.lastname: Benshoff
authors.forename: B
authors.initials: B
authors.lastname: Olack
authors.forename: S
authors.initials: S
authors.lastname: Shenoy
authors.forename: M D
authors.initials: MD
authors.lastname: Jendrisak
authors.forename: W C
authors.initials: WC
authors.lastname: Chapman
authors.forename: T
authors.initials: T
authors.lastname: Mohanakumar
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D053477:Apoptotic Protease-Activating Factor 1 / Q000378:metabolism; D002135:Calcium-Binding Proteins; D020169:Caspases / Q000378:metabolism; D045304:Cytochromes c / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D005466:Fluorocarbons / Q000494:pharmacology*; D005786:Gene Expression Regulation; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins; D007515:Islets of Langerhans / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D016381:Islets of Langerhans Transplantation; D008840:Microfilament Proteins; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000378:metabolism; D019188:Organ Preservation Solutions / Q000494:pharmacology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D000077022:Survivin
chemical_list: C112986:AIF1 protein, human; C506592:APAF1 protein, human; D053477:Apoptotic Protease-Activating Factor 1; C107489:BIRC5 protein, human; D002135:Calcium-Binding Proteins; D004268:DNA-Binding Proteins; D005466:Fluorocarbons; D051034:Inhibitor of Apoptosis Proteins; D008840:Microfilament Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D019188:Organ Preservation Solutions; D019253:Proto-Oncogene Proteins c-bcl-2; D000077022:Survivin; D045304:Cytochromes c; D020169:Caspases