Effects of transfection of rat hemeoxygenase-1 on expression of Toll-like receptor 4 during myocardial ischemia-reperfusion injury in rats

Abstract

Objective To investigate the effect of rat hemeoxygenase-1 (rHO-1) gene carried by recombinant adeno-associated virus (rAAV) on expression of Toll-like receptor 4 (TLR4) during myocardial ischemia-reperfusion (IR) injury in rats.Methods rHO-1 carry gene rAAV carrier was constructed,then transfected into rat myocardial cells.After 3 months,the expression of HO-1 mRNA in the injected myocardium was detected by using reverse transcription-polymerase chain reaction (RT-PCR).After the successful reproduction of the myocardial IR model,the animals were killed and their hearts were harvested for determination of myocardial infarct size and pathological changes in myocardial tissue.The expression of TLR4,tumor necrosis factor-α (TNF-α) and nuclear factor-κB (NF-κB) was detected by using Western blotting.Results The expression of HO-1 mRNA was significantly higher,and the infarct size was significantly smaller in rAAV-rHO-1 group than in group IR (both P ＜0.05 ).The expression of TLR4,TNF-α and NF-κB was significantly increased in IR group (0.45 ±0.03,0.42 ±0.05,and 0.46 ±0.07 respectively) and rAAV-rHO-1 group (0.33 ±0.04,0.36 ±0.02,and 0.33 ±0.03 respectively) as compared with rAAV-rHO-1 group ( all P ＜0.05 ).The degree of damage to myocardial tissue was significantly severer in IR group than in SO group and rAAV-rHO-I group.Conclusion rAAV-mediated rHO-1 gene trans-fection may attenuate myocardial IR injury by reducing the TLR4 expression level and inhibiting the inflammatory response in rats. Key words: Heme oxygenase; Myocardial reperfusion injury; Gene transfection; Adenoviridae; Toll-like receptor 4