Protective Effects of Erythropoietin and N-Acetylcysteine on Methotrexate-Induced Lung Injury in Rats

Objective: Methotrexate (MTX) is known to have deleterious side effects on lung tissue. We aimed to investigate the effects of erythropoietin (EPO) and N-acetyl-cysteine (NAC) on MTX-induced lung injury in rats. Study Design: Animal experiment. Material and Methods: Twenty-six female Sprague-Dawley rats were divided into 4 groups. Sham group, 0.3 mL saline; MTX group, 5 mg/kg MTX; EPO group, 5mg/kg MTX and 2000 IU/kg EPO; NAC group, 5 mg/kg MTX and 200 mg/kg NAC were administered once daily for 4 consecutive days. Malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT) and inflammation and congestion scores in lung tissues were evaluated. Results: In MTX group MDA were significantly higher, CAT and SOD were significantly lower than in sham, EPO and NAC groups (p 0.005). In EPO group MDA, CAT, and SOD were higher, but not significant than those in group NAC (p 0.005). In group MTX both scores were significantly higher than in sham (p 0.005). The congestion score of group MTX was significantly higher than those of group EPO and NAC (p 0.005). Conclusion: EPO and NAC have significant preventive effects on MTX-induced lung injury in rats. Decreased antioxidant capacity and increased MDA level may cause the oxidative damage in MTX group. Also, higher antioxidant capacity and lower MDA level may be a response to oxidative stress in EPO and NAC groups.