Protective effect of RNA interfering tumor necrosis factor-α in Kupffer cells on liver ischemic reperfusion injury in rats

Objective To investigate the protective effect of silencing tumor necrosis factor-α (TNF-α) gene in Kupffer cells on liver ischemic reperfusion injury in rats. Methods We constructed the eukaryotic expression vector of small hairpin RNA targeting rat TNF-α gene. PBS, blank vector or TNF-α shRNA mixture were injected through portal vein 48 h before operation. The animals were divided into 4 groups: sham group, PBS group, blank vector group, and shRNA group. The left lateral and median lobes of the liver were rendered ischemic for 40 min resulting in a segmental (70 %) hepatic ischemia. The serum ALT and AST levels were determined 6 h after reperfusion. The mRNA expression of TNF-α in Kupffer cells, serum TNF-α level, concentration of the malondialdehyde (MDA) and superoxide dismutase(SOD) in the liver tissue were detected. Results Compared with the PBS and blank vector groups, ALT and AST levels were significantly decreased in the shRNA group after reperfusion for 6 h (P＜0. 05), TNF-α mRNA level, serum TNF-α level(56.6 ± 6. 7 pg/ml vs 87.8 ± 8. 7 pg/ml and 96.5±7.3 pg/ml,P＜0. 05), concentration of MDA in the liver tissue(93.4±13.3 nmol/mg vs 133.5±12. 4 nmol/mg and 136.7 ±13. 6 nmol/mg, P＜0.05 )were significantly decreased, and SOD activity was significantly increased(22.4±4.6 U/mg vs 12. 2±3. 1 U/mg and 11. 4±2. 9 U/mg,P＜0. 05). Conclusion RNA interfering TNF-α gene in Kupffer cells can protect the liver against ischemia/reperfusion injury. Key words: Reperfusion injury;  Liver;  Tumor necrosis factor;  Kupffer cells;  RNA interference