Context: Tacrolimus (TAC), a calcineurin inhibitor, is commonly used as an immunosuppressive agent in organ transplantation, but its clinical use may be limited due to cardiotoxicity. Olmesartan (OLM; angiotensin receptor blocker) and aliskiren (ALK; renin inhibitor) may attenuate cardiotoxicity induced by TAC by inhibition of renin-angiotensin aldosterone system.
Objective: The aim of this study was to evaluate the effect of OLM and ALK on TAC-induced cardiotoxicity.
Materials and methods: Male Wistar albino rats weighing 200-250 g (10-12 weeks old) were used in this study. Animals were divided into four groups. Group 1 received normal saline, group 2 received TAC (2 mg/kg, intraperitoneally for 14 d), group 3 received OLM (2 mg/kg, p.o. for 28 d) + TAC and group 4 received ALK (50 mg/kg, p.o. for 28 d) + TAC. TAC-induced cardiotoxicity was assessed biochemically and histopathologically.
Results: Treatment with OLM or ALK decreased the TAC-induced changes in biochemical markers of cardiotoxicity such as serum aspartate transaminase, creatine kinase and lactate dehydrogenase. OLM or ALK also attenuated the effects of TAC on oxidant-antioxidant parameters such as malondialdehyde, reduced glutathione and catalase. Histopathological and ultrastructural studies showed that OLM or ALK also attenuated TAC-induced cardiotoxicity.
Discussion and conclusion: These results suggest that OLM as well as ALK has protective effects against TAC-induced cardiotoxicity; implying that angiotensin receptor blocker or renin inhibitor, respectively, may counteract cardiotoxicity associated with immunosuppressant use.
Keywords: Angiotensin receptor blocker; aliskiren; cardiotoxicity; olmesartan; renin angiotensin aldosterone system; renin inhibitor; tacrolimus.