Antifibrotic effect of captopril and enalapril on paraquat‐induced lung fibrosis in rats

Abstract

Although different treatment modalities have been implemented for pulmonary fibrosis, the results have not been promising and these conditions have been considered untreatable and irreversible. Thus, a plethora of new drugs has been tried for the control of this condition in recent years. This study examined the effects of two angiotensin-converting enzyme inhibitors, captopril and enalapril, on paraquat-induced pulmonary fibrosis in rats, through biochemical and histopathological parameters. Male albino Wistar rats were divided into eight groups (n = 4-5 each), including control, paraquat, captopril alone, captopril treatment and pre-treatment, enalapril alone, enalapril treatment and pre-treatment. After 21 days of treatment, the lungs were removed and the levels of hydroxyproline, glutathione and lipid peroxidation were determined. Angiotensin-converting enzyme inhibitors showed no effect on glutathione and lipid peroxidation. The results also demonstrated that captopril and enalapril improved pulmonary fibrosis as shown by histopathology, as well as a decreased content of hydroxyproline (P < 0.001) in the lung tissue. In conclusion, the present findings suggest that the antifibrotic effect of these drugs may be related to the inhibition of angiotensin-converting enzyme.

Protective Effect of Ambroxol against Paraquat-induced Pulmonary Fibrosis in Rats

“…Reduction of lipid peroxidation may contribute to its protective effect in lung tissue. Some studies aiming at using antioxidants such as melatonin, enalapril and captopril have demonstrated that these antioxidants could provide some prevention of the fibrogenic effect of paraquat (19,20). Our investigation of ambroxol is consistent with their conclusions.…”

Effect of transforming growth factor-β1 on acute lung injury caused by paraquat

“…Paraquat is known to induce toxicity in cells by stimulating oxygen utilization via redox cycling and the generation of reactive oxygen intermediates (10)(11)(12). However, the exact role of paraquat in the progression of pathogenesis has not been clearly established (13)(14)(15).…”

Protective Effect of Valsartan on Beleomycine-Induced Fibrosis

“…Yao et al investigated the anti-fibrotic effect of losartan and found that the protective effect of losartan may be associated with its antifree radicals and the reduction in TGF-β1 (23). The results of Ghazi-Khansari et al's work (24) showed that captopril and enalapril improved pulmonary fibrosis in histopathological studies as well as decreasing collagen content in the lung tissue. Marut et al's research (25) on irbesartan as an AT1 blocker indicated a protective effect of irbesartan by the inhibition of inflammation and NO production.…”