title: Intratracheal administration of p38α short-hairpin RNA plasmid ameliorates lung ischemia-reperfusion injury in rats.
abstract: BACKGROUND
  Lung ischemia-reperfusion injury (LIRI) remains a significant problem after lung transplantation. A crucial signaling enzyme involved in inflammation and apoptosis during LIRI is p38 mitogen-activated protein kinase (MAPK). Gene silencing of p38α by short hairpin RNA (shRNA) can downregulate p38α expression. The lungs have an extremely large surface area, which makes the absorption of shRNA highly effective. Therefore, we evaluated the therapeutic efficacy of p38α shRNA plasmids in a rat model of lung transplantation.
  
  
  METHODS
  The delivery of p38α shRNA plasmid was performed by intratracheal administration 48 hours before transplantation into donor rats. Control animals received scrambled shRNA plasmids. Reverse-transcription polymerase chain reaction and Western blots were used to assess gene silencing efficacy. The therapeutic effects of shRNA plasmids were evaluated by lung function tests. We determined the levels of inflammatory cytokines, the level of intercellular adhesion molecule 1 (ICAM-1), c-Myc mRNA expression, and ICAM-1 protein expression, and the presence of cell apoptosis.
  
  
  RESULTS
  Rats administered p38α shRNA plasmids showed a significant downregulation in lung expression of p38α transcripts and protein levels. Compared with the control group, the p38α shRNA group showed a higher pulmonary vein oxygen level, lower wet weight-to-dry weight ratio, lower lung injury score, and lower serum levels of tumor necrosis factor-α, interleukin-6, and interleukin-8. Messenger RNA levels of ICAM-1 and c-Myc in the p38α shRNA group were dramatically lower than in the control group. Levels of ICAM-1 protein expression exhibited a similar trend. Cell apoptosis decreased in the p38α shRNA group vs the control group.
  
  
  CONCLUSIONS
  Intratracheal administration of p38α shRNA plasmids provided therapeutic effects in a rat model of lung transplantation.
authors.affiliation: Department of Anesthesiology, Hei Long Jiang Province Key Lab of Research on Anesthesiology and Critical Care Medicine, and Second Affiliated Hospital, Harbin Medical University, Harbin, China.
authors.forename: Xiangqi
authors.initials: X
authors.lastname: Lv
authors.forename: Jing
authors.initials: J
authors.lastname: Tan
authors.forename: Dongdong
authors.initials: D
authors.lastname: Liu
authors.forename: Ping
authors.initials: P
authors.lastname: Wu
authors.forename: Xiaoguang
authors.initials: X
authors.lastname: Cui
mesh_terms: D000818:Animals; D017209:Apoptosis; D016207:Cytokines / Q000097:blood; D066298:In Vitro Techniques; D007249:Inflammation / Q000473:pathology; D007267:Injections; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D007442:Intubation, Intratracheal; D008168:Lung / Q000098:blood supply* / Q000378:metabolism / Q000473:pathology; D016040:Lung Transplantation; D008297:Male; D048290:Mitogen-Activated Protein Kinase 11 / Q000037:antagonists & inhibitors* / Q000235:genetics; D023421:Models, Animal; D010957:Plasmids / Q000008:administration & dosage* / Q000627:therapeutic use*; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism; D034741:RNA, Small Interfering / Q000008:administration & dosage* / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*
chemical_list: D016207:Cytokines; D016271:Proto-Oncogene Proteins c-myc; D034741:RNA, Small Interfering; D018799:Intercellular Adhesion Molecule-1; D048290:Mitogen-Activated Protein Kinase 11