Effect of telmisartan in amelioration inflammatory responses induced by myocardial ischemia reperfusion injury IN male mice

Abstract EN

Background: Myocardial ischemia–reperfusion represents a clinically relevant problem associated with thrombolysis, angioplasty and coronary bypass surgery.

Angiotensin II may contribute to reperfusion injury by increasing oxidative stress and inflammatory factors .

Ang II exerts most of its effects via AT1Rs.

Apoptosis of cardiomyocytes may further be influenced by Ang II.

Objective: This study was undertaken to investigate the potential role of Telmisartan in amelioration of myocardial I/R injury induced by ligation of coronary artery in mouse model.

Materials & method: Adult male Swiss-albino mice were randomized into 4 equal groups.

Group (1) sham group: Mice underwent the same anesthetic and surgical procedure as the active control group except ligation of LAD coronary artery.Group( 2) active control group: Mice were subjected to regional ischemia for 30 min by ligation of LAD coronary artery and reperfusion for 2 hours .Group( 3) control vehicle group (1): Mice in this group injected with DMSO (vehicle for Telmisartan ) via IP route & underwent Myocardial ischemia for 30 minutes by ligation of (LAD) coronary artery & reperfusion for 2 hr .

Group (4)Telmisartan treated group : Mice pretreated with Telmisartan 0.5mg/kg i.p 30 minutes before ligation of LAD coronary artery.

Results: Compared with the sham group, Levels of TNF-α & IL-1β, IL-6,caspase 3 and plasma level of cardiac troponin I increased in control group (p<0.001).Levels of Bcl2 decreased in control group(p<0.001).

Histologically ,All mice in control group showed a significant (p<0.001) cardiac injury.

Telmisartan significantly counteract the increase in myocardium level of TNF-α, IL-1B,IL-6,caspase 3 ,plasma cTnI (P < 0.001).

Furthermore, the Telmisartan significantly increased in myocardium level of Bcl2.

Histological analysis revealed that both Telmisartan markedly reduced (P < 0.001) the severity of cardiac injury in the mice underwent LAD ligation procedure .

Conclusion: The results of the present study reveal that Telmisartan may ameliorate myocardial I/R injury in Male Mice via interfering with inflammatory reactions & apoptosis which induced by I/R injury