Methotrexate (MTX) is a commonly used antineoplastic and anti-rheumatoid drug whose efficacy is limited by its hepatotoxicity. The aim of this study was to investigate the possible protective role of captopril (100 mg/kg/day, p.o. for seven days), an angiotensin converting enzyme inhibitor, and telmisartan (10 mg/kg/day p.o. for seven days), an angiotensin II receptor blocker with peroxisome proliferative receptor gamma (PPARγ) agonism, in a model of MTX (single dose 20 mg/kg i.p. at the fifth day) induced hepatotoxicity in rats. Results of the present study revealed MTX-induced hepatotoxicity as demonstrated by increased level of liver enzymes and confirmed by histopathology. Pretreatment with captopril or telmisartan produced a significant hepatic protection manifested as a significant (p < 0.05) decrease in serum levels of alanine transferase (ALT) and aspartate transferase (AST) and alkaline phosphatase (ALP) enzymes; hepatic malondialdehyde (MDA) and total nitrites and nitrates (NOx) levels; as well as a significant increase in hepatic superoxide dismutase (SOD) activity. In addition, there was a remarkable improvement in the histopathological features and a significant reduction in the expression of COX-2, iNOS and caspase-3 enzymes as compared with the MTX group. We recommend considering captopril/Telmisartan, if tolerated and not contraindicated, as preferable antihypertensive agents in patients receiving MTX in their chemotherapy protocols.
Keywords: Captopril; hepatotoxicity; methotrexate; telmisartan.