Small interfering RNA targeting heme oxygenase-1 enhances ischemia-reperfusion-induced lung apoptosis.
Heme oxygenase-1 (HO-1) is emerging as an important cytoprotective enzyme system in a variety of injury models. To optimize future therapeutic applications of HO-1, it is necessary to delineate the precise functions and mechanisms as well as modes of externally regulating HO-1 expression. Investigations have been limited by difficulties with the generation of HO-1 null mice and the lack of specific HO-1 inhibitors. Lung ischemia-reperfusion (I-R) injury is the inciting event in acute lung failure following transplantation, surgery, and shock. To study the function of HO-1 in I-R-induced lung injury, we designed small interfering RNA (siRNA) sequences that effectively suppress HO-1 expression both in vitro and in vivo in an organ-specific manner. In this study we show that there is enhanced apoptosis, via increased Fas expression and caspase 3 activity, in the presence of HO-1 siRNA in endothelial cells and mouse lung during I-R injury, whereas HO-1 overexpression attenuates apoptosis. To the best of our knowledge, we are the first to demonstrate that lung-specific siRNA delivery can be achieved by intranasal administration without the need for viral vectors or transfection agents in vivo, thereby obviating potential concerns for toxicity if siRNA technology is to have clinical application in the future.
Zhang
Xuchen
X
Section of Pulmonary and Critical Care Medicine, Yale University School of Medicine, New Haven, Connecticut 06520-8057, USA.
Shan
Peiying
P
Jiang
Dianhua
D
Noble
Paul W
PW
Abraham
Nader G
NG
Kappas
Attallah
A
Lee
Patty J
PJ
D000818:Animals; D017209:Apoptosis; D015153:Blotting, Western; D053148:Caspase 3; D020169:Caspases / Q000096:biosynthesis; D002460:Cell Line; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism; D005434:Flow Cytometry; D006419:Heme Oxygenase (Decyclizing) / Q000235:genetics*; D051547:Heme Oxygenase-1; D000860:Hypoxia; D019194:Ischemic Preconditioning; D008168:Lung / Q000378:metabolism / Q000473:pathology*; D008171:Lung Diseases / Q000473:pathology; D008297:Male; D008565:Membrane Proteins; D051379:Mice; D008810:Mice, Inbred C57BL; D010100:Oxygen / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics* / Q000378:metabolism; D051381:Rats; D015427:Reperfusion Injury; D013997:Time Factors; D014018:Tissue Distribution; D014162:Transfection; D019014:fas Receptor / Q000096:biosynthesis
D008565:Membrane Proteins; D034741:RNA, Small Interfering; D019014:fas Receptor; D006419:Heme Oxygenase (Decyclizing); D051547:Heme Oxygenase-1; C496542:Hmox1 protein, mouse; C505409:Casp3 protein, mouse; C505410:Casp3 protein, rat; D053148:Caspase 3; D020169:Caspases; D010100:Oxygen