Isoform-specific functions of c-Jun N-terminal kinase 1 and 2 in lung ischemia-reperfusion injury through the c-Jun/activator protein-1 pathway
- J Thorac Cardiovasc Surg. 2021 Aug;162(2):e143-e156. doi: 10.1016/j.jtcvs.2020.03.083.
- 1. Department of Anesthesiology, Hei Long Jiang Province Key Lab of Research on Anesthesiology and Critical Care Medicine, Second Affiliated Hospital, Harbin Medical University, Harbin, China.
- 2. Department of Anesthesiology, Hei Long Jiang Province Key Lab of Research on Anesthesiology and Critical Care Medicine, Second Affiliated Hospital, Harbin Medical University, Harbin, China; Department of Anesthesiology, First Affiliated Hospital, Hainan Medical University, Hainan, China. Electronic address: [email protected].
Background: c-Jun N-terminal kinase 1 (JNK1) and JNK2 regulate distinct pathological processes in lung diseases. Here we discriminated the respective roles of these kinases in lung transplantation-induced ischemia-reperfusion injury (IRI).
Methods: Rat pulmonary microvascular endothelial cells were transfected with JNK1 small-interfering RNA (siRNA) and JNK2 siRNA and then subjected to in vitro IRI. For the isoform confirmed to aggravate IRI, the delivery of short-hairpin RNA (shRNA) plasmid was performed by intratracheal administration 48 hours before transplantation into donor rats. After a 3-hour reperfusion, the samples were collected.
Results: JNK1 siRNA decreased but JNK2 siRNA increased JNK phosphorylation and activity, phosphorylated and total c-Jun, and activator protein-1 activity. Although JNK1 siRNA decreased Apoptosis and the levels of malondialdehyde, interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF-α), it increased the levels of superoxide dismutase, S-phase percentage, and cyclin D1; JNK2 siRNA had a converse effect. JNK1 siRNA decreased the level of Lactate Dehydrogenase and increased the levels of VE-cadherin, nitric oxide, phosphorylated nitric oxide synthase, and cell viability; JNK2 si RNA had a converse effect. Compared with the control group, the JNK1 shRNA group exhibited a higher lung oxygenation index and lower lung Apoptosis index, injury score, wet weight:dry weight ratio, and levels of IL-1, IL-6, and TNF-α.
Conclusions: JNK1 aggravated, but JNK2 alleviated, IRI through differential regulation of the JNK1 pathway in in vitro ischemia-reperfusion. JNK1 silence attenuated lung graft dysfunction by inhibiting inflammation and Apoptosis. These findings provide a theoretical basis for devising therapeutic strategies against IRI after lung transplantation.