[Poly (ADP-ribose) polymerase inhibition attenuates ischemia/reperfusion induced myocardial injury in rat via reducing myocardial nuclear factor κB activity].

Objective: To investigate the effect of Poly (ADP-ribose) polymerase (PARP) inhibition on ischemia/reperfusion (I/R) induced myocardial injury in rat and related mechanisms.
Method: Adult Wistar rats were randomly divided into sham-control (n = 18), I/R (60 min ischemia followed by 180 min reperfusion, n = 18) and I/R + PARP inhibitor 3,4-dihydro-5-[4-(1-piperidinyl)butoxy]-1(2H)-isoquinolinone (DPQ), 10 mg/kg, i.p. injection at 1 h before I/R (n = 18). Myocardial expression of PARP, infarct size, and cardiomyocytes apoptosis were determined. Additionally, myocardial NF-κB activity and the myocardial expressions of ICAM-1, COX-2 and MMP-9 at protein and mRNA level were detected.
Result: (1) Myocardial expression of PARP was significantly upregulated in I/R group compared to sham-control group, which could be significantly reduced by pretreatment with DPQ (P < 0.05 vs. I/R group). (2) Infarct size [(31.45 ± 5.54)% vs. (45.97 ± 4.22)%] and cardiomyocytes apoptosis [(23.0 ± 3.8)% vs. (34.0 ± 6.2)%] were significantly reduced by pretreatment with DPQ (all P < 0.05 vs. I/R group). (3) Pretreatment with DPQ also significantly decreased the NF-κB activity and the myocardial expressions of ICAM-1, COX-2 and MMP-9 at both protein and mRNA level (all P < 0.05).
Conclusion: The expression of PARP, NF-κB activity and the myocardial expressions of ICAM-1, COX-2 and MMP-9 are upregulated in I/R induced myocardial injury. PARP inhibitor DPQ could attenuate I/R induced myocardial injury through reducing NF-κB activity and the myocardial expressions of ICAM-1, COX-2 and MMP-9.