title: Cystamine prevents ischemia-reperfusion injury by inhibiting polyamination of RhoA.
abstract: Transglutaminase2 (TGase2) activates Rho-associated kinase (ROCK), an important mediator of ischemia-reperfusion (IR) injury, through polyamination of RhoA. Cystamine, an oxidized dimer of cysteamine inhibits the transamidation activity of TGase2. We examined whether addition of cystamine to an organ preservation solution protects rat cardiomyocyte cells (H9C2) from cell death in IR injury. H9C2 cells were stored under hypoxic conditions at 4 degrees C in laboratory-made preservation solution (SNU) or SNU solution supplemented with cystamine (SNU-C1), and cell preservation in the two solutions was compared by measuring the release of lactate dehydrogenase. The cells were preserved more effectively in SNU-C1 than in SNU solution. Cystamine inhibited the intracellular activity of TGase2 which increased during cold storage or reoxygenation. The inhibition of TGase2 by cystamine reduced the polyamination of RhoA, the interaction between RhoA and ROCK2, and F-actin formation. Cystamine also prevented the activation of caspases during cold storage. These results suggest that addition of cystamine to the organ preservation solution significantly enhances cardiomyocytes preservation apparently by inhibiting TGase2-mediated RhoA-ROCK pathway and that TGase2 may play an important role in IR injury by regulating ROCK.
authors.affiliation: Xenotransplantation Research Center (XRC), Seoul National University College of Medicine, 28 Yongon-Dong, Chongno-Gu, Seoul 110-799, Republic of Korea.
authors.forename: Dong-Myung
authors.initials: DM
authors.lastname: Shin
authors.forename: Jinmo
authors.initials: J
authors.lastname: Kang
authors.forename: Jongwon
authors.initials: J
authors.lastname: Ha
authors.forename: Heun-Soo
authors.initials: HS
authors.lastname: Kang
authors.forename: Sang-Chul
authors.initials: SC
authors.lastname: Park
authors.forename: In-Gyu
authors.initials: IG
authors.lastname: Kim
authors.forename: Sang Joon
authors.initials: SJ
authors.lastname: Kim
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002460:Cell Line; D003080:Cold Temperature; D003538:Cystamine / Q000032:analysis / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000032:analysis / Q000494:pharmacology*; D019204:GTP-Binding Proteins / Q000037:antagonists & inhibitors*; D007770:L-Lactate Dehydrogenase; D032383:Myocytes, Cardiac / Q000187:drug effects* / Q000201:enzymology; D019188:Organ Preservation Solutions / Q000737:chemistry / Q000494:pharmacology*; D011073:Polyamines / Q000378:metabolism; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D051381:Rats; D015427:Reperfusion Injury / Q000201:enzymology*; D011503:Transglutaminases / Q000037:antagonists & inhibitors*; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D020742:rhoA GTP-Binding Protein / Q000378:metabolism
chemical_list: D004791:Enzyme Inhibitors; D019188:Organ Preservation Solutions; D011073:Polyamines; D007770:L-Lactate Dehydrogenase; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases; D054460:rho-Associated Kinases; D019204:GTP-Binding Proteins; D020742:rhoA GTP-Binding Protein; D003538:Cystamine