title: Mechanisms of islet damage mediated by pancreas cold ischemia/rewarming.
abstract: Prolonged pancreas cold ischemia is known to negatively correlate with islet isolation outcomes, hindering successful islet transplantation to treat Type-1 Diabetes. Due to poor islet isolation outcome, pancreata with over 16 h cold ischemia are currently not considered for islet transplantation. Mechanisms involved in pancreas cold ischemia/rewarming mediated islet damage during islet isolation and culture are not well understood. Using an en bloc cold preserved rat pancreas preparation, we attempted to clarify possible mechanisms of islet death associated with prolonged pancreas cold ischemia and subsequent rewarming. Cold ischemia lasting 16 h decreased post-isolation islet yield and increased islet death during the initial 6 h of culture. Electron micrographs revealed swelling and severe disruption of cellular and mitochondrial membranes, as well as an enlarged endoplasmic reticulum (ER) in β-cells isolated from cold preserved pancreata. Prolonged cold ischemia of the pancreas transiently activated mitogen-activated protein kinases (MAPKs) in isolated islets and increased lipid peroxidation products 4-hydroxynonenal (HNE) and heat shock protein (Hsp) 70 after culture, indicating the activation of oxidative stress signaling pathways. The islet isolation process, irrespective of pancreas cold ischemia, activated unfolded protein response (UPR), while the ER protective chaperon BiP was further upregulated by pancreas cold ischemia/rewarming. During the first 6 h of culture following islet isolation, p53 upregulated modulator of apoptosis (Puma) and caspase-3 activation were also upregulated. Our study indicates the involvement of both apoptosis and necrosis in islet death, and suggests oxidative stress and disruption of membranes are critical mechanisms mediated by pancreas cold ischemia/rewarming.
authors: Division of Developmental and Translational Diabetes and Endocrinology Research, Department of Diabetes and Metabolic Researches, Beckman Research Institute of City of Hope, 1500 East Duarte Rd, Duarte, CA 91010, USA. Electronic address: komori@coh.org.
authors: Keiko
authors: K
authors: Omori
authors: Center for Development of Advanced Medical Technology, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke-shi, Tochigi, 329-0498, Japan; Department of Organ Fabrication, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.
authors: Eiji
authors: E
authors: Kobayashi
authors: Division of Developmental and Translational Diabetes and Endocrinology Research, Department of Diabetes and Metabolic Researches, Beckman Research Institute of City of Hope, 1500 East Duarte Rd, Duarte, CA 91010, USA.
authors: Jeffrey
authors: J
authors: Rawson
authors: Division of Inflammation Research, Center for Molecular Medicine, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke-shi, Tochigi, 329-0498, Japan.
authors: Masafumi
authors: M
authors: Takahashi
authors: Division of Developmental and Translational Diabetes and Endocrinology Research, Department of Diabetes and Metabolic Researches, Beckman Research Institute of City of Hope, 1500 East Duarte Rd, Duarte, CA 91010, USA.
authors: Yoko
authors: Y
authors: Mullen
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D053148:Caspase 3 / Q000378:metabolism; D002478:Cells, Cultured; D050377:Cold Ischemia / Q000379:methods*; D015925:Cryopreservation; D004721:Endoplasmic Reticulum / Q000473:pathology; D004789:Enzyme Activation; D007328:Insulin; D050417:Insulin-Secreting Cells / Q000166:cytology / Q000473:pathology*; D016381:Islets of Langerhans Transplantation / Q000379:methods*; D008297:Male; D051336:Mitochondrial Membranes / Q000473:pathology; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009842:Oligopeptides / Q000378:metabolism; D009926:Organ Preservation / Q000379:methods; D018384:Oxidative Stress / Q000502:physiology*; D011887:Raffinose; D051381:Rats; D011917:Rats, Inbred Lew; D017694:Rewarming / Q000379:methods*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D056811:Unfolded Protein Response / Q000502:physiology
chemical_list: C539791:Bax-inhibiting peptide, BIP; D007328:Insulin; D009842:Oligopeptides; D016159:Tumor Suppressor Protein p53; D020928:Mitogen-Activated Protein Kinases; D053148:Caspase 3; D011887:Raffinose
keywords: 4-Hydroxynonenal; Cold ischemia-rewarming; ER stress; Islet apoptosis; Islet isolation; Islet transplantation; Oxidative stress; Puma